Common problems, symptoms and remedies
From DucatiWiki
Please help clean it up if you are able.
Common problems, symptoms and remedies
Part of the “experience”, or “charm” of owning a Ducati is that they can (and do) have the occasional problem. There are a few known problems, which affect specific models. These are shown briefly in the table below, and discussed in more detail later on.
This is not an exhaustive list, nor does the list imply that you will ever experience any or all of these problems, and some owners might report a “once off” type of problem which is peculiar to their bike. The list below consists of generally known and accepted problems.
Items in the table below are in no particular order, and for any given bike, you may not experience any of them. If you experience all of them, then you are the world’s unluckiest owner!
| Fault | Symptoms | Models affected |
|---|---|---|
| Regulator Problems | Unsteady voltage, Frequent flat battery | 98 ST2 |
| Clutch Slave Cylinder | Fluid leak / discolouration
Difficult to find neutral, or shift gear. Excessive free play|| | |
| Clutch Groan | Loud groaning noise when engaging the clutch | |
| Rear Engine Bolt | Frame Cracking, bolt breaking | |
| Clutch Wear | Noise from the clutch - clunks, groans, etc. | |
| Fogging headlight | Cloudy lens, condensation on inside of headlight | |
| Loose alternator nut | Clutch Noise Vibration through the handlebars | |
| Chain Tensioner Warning | ||
| Fuel pump relay | Bike won’t go (really?) No fuel pump noise when ignition is turned on | |
| Counter shaft sprocket retainer clip | Pre 2000 | |
| Help! My bike won’t start! | Errr….. bike won’t start? | |
| Sluggish Starting | Bike kicks over slowly before starting | |
| 916 Rocker arm wear | Poor performance, engine running badly, timing problems,etc. | ST4 |
| That annoying rattle | That annoying rattle | |
| Spongy brake lever | Spongy Brake lever | |
| Front brake lever hits fairing | On full left steering lock, the front brake lever hits the fairing | |
| Lack of freeplay in the front brake lever | Lack of freeplay in front brake lever - perhaps after a service,
or some brake work, front brake seems to be locked partially on (yikes!) | |
| Battery light comes on intermittently | Battery light comes on occasionally | ST’s with a
battery light |
| Temperature Problems | Temperature too high | |
| Rear brake line warning | Potential to wear through by rubbing against the carrier | ST2 only? |
| Spluttering and Stalling | Your bike misfires, splutters, and sometime stalls. Could it be…. | |
| Cylinder Base Gasket | Leak You notice oil coming from the base of the rear cylinder | ST4 |
| Exhaust popping and/or occasional backfire | Technical term here is exhaust farting….. | All |
| Bike runs poorly, won’t rev over about 5000 rpm | Bike runs poorly, won’t rev over about 5000 rpm | All |
| Rusty Steering Head | Bearings Rusty steering head bearings | All |
Regulator
A few owners have reported electrical problems with their ST (Electrical problems on a Ducati? Oh no….!). Many of the problems are related to loose connections, or an occasional faulty regulator. Another theory is that the older regulators are not able to handle the heat of the newer items, and being buried inside the fairing, there’s no airflow - the result being cooked (or partially cooked = flaky) regulators.
Older ST models have a battery light which will shine if there are problems. If your bike has problems with a constant flat battery, but the battery seems ok, or you have other gremlins… check the regulator.
The following tip comes from AJ:
“If you have meter, try measuring the voltage when you ride, it should read something around 12.5-13 on idle and <1500rpm, then above 2000rpm it should settle around 14.1-14.4. If the voltage looks flaky then you should look at the regulator.”
The following hint comes from Chris Kirk:
“Did a bit of hitchhiking after the ST2 wouldn’t re-fire when I stopped to clean my visor after motoring through a brief but fierce hailstorm. Thought the regulator was cooked since it was showing no output so Steve @ SLMS is sending me a replacement. When doing some R&M while the fairings were off I did a thorough check of the regulator wiring & found corrosion had fried the internals of one of the two plug in regulator connectors to the alternator and a wire that looked connected in fact was not. Last night I hard wired the three yellow wires between the alternator/stator with soldered connections and protected the connections heat shrieked insulator wraps. The output is now marginally normal with13.88v @ 3K
So next time you guys have the fairings off, I’d suggest it might be worthwhile checking & cleaning the alternator/stator to regulator connections. A little dielectric grease on hand wouldn’t hurt.”
The regulator problem seems to be most prevalent on the 98 model ST2. Some owners have had the regulator replaced a number of times. An alternate to the standard regulator is the item by “Electrex”. Some work will be required to fit the non-standard item, as the mounting points are different.
Ruudje provides another alternative:
“Yes your regulator will be gone soon. But.... it can be operative for a year or more...no-one knows.
Replace it for peace of mind and stock it for future use in emergency situation. That is what I did. I
take it on longer trips.
The Electrex RR51 may die on your ST also. Even sooner as the original one did.
The Ducati replacement is better but expensive. Use a SH232-12 or SH538-12 from a totalled Honda, models CB125/250 of VF500. Other Honda models may have used the same regulator but from these models I know for sure. A used regulator will cost you not a lot more than $50 as the Duc replacement goes for about 200.”
Clutch Slave Cylinder
Many (many!) owners report problems with leaking clutch slave cylinders. The leaking can be very minor,
not always obvious on the outside, but have a major impact on clutch performance. The symptoms are
varied, but in my case I had difficulty changing gears (especially down), couldn’t find neutral, had a really
mushy clutch lever feel, and a slight fluid discolouration.
The main culprit is generally accepted to be chain gunk fouling the shaft, which then wears out the seals.
Ducati have a revised cylinder with a longer skirt to keep the chain gunk away, but owners of new bikes
still report problems.
Interestingly, owners who have replaced their cylinders with an after market item such as Yoyodyne or
VeeTwo don’t report these problems.
Replacement clutch slave cylinder seals called “Quad Ring” are available for many Ducati models.
These seals are available mail order, in the UK from authorised Ducati Performance agents, Pro Twins,
for £ 2.50 + VAT inclusive of postage. This is good value bearing in mind that the shorter-lived OEM seal
from Ducati is a similar price. Their postal address is: Lambs Business Park, Tilburstow Hill Road, South
Godstone, Surrey, RH9 8LJ England.
Telephone: 01342 892888 fax: 01342 893996 e-mail: <[mail@protwins.co.uk]>
Replacement slave cylinders are also available from Evoluzione, Vee Two and Yoyodyne
Ray provides some great information on clutch slave cylinder failures:
“Now, I know on the early models a lot of people were questioning whether contamination of the inner seals by chain lube/ gunk/ grit was causing the problem of seal failure/ wear. Anyone who has owned a '01 model with the same problem can tell you that this is definitely not the case. The '01 has a green silicone high temperature seal between the slave cylinder housing and the gearbox casting. This is a very tight seal and would not let fluids or contaminants enter or exit the slave cylinder.
The fact that the '01 models have this seal gives an explanation as to why failure symptoms differ slightly between model years.
On the earlier models without the housing seal the clutch fluid will leak out of the rear of the cylinder housing (assuming the piston seal fails) and onto the gearbox casting, a resultant loss of fluid will be observed in the master cylinder and the clutch action will have less "feel" due to air possibly entering the system via the leaky seal. Also, the clutch will become more difficult to disengage due to the compounded effect of "compressible" air in the system and the leak of fluid (and hence the loss of piston travel) during clutch operation.
On later models with the housing seal (again assuming the piston seal fails), the clutch fluid leaks past the piston seal and then is prevented from escaping any further due to the housing seal and the O-rings on the clutch pushrod where it enters the gearbox through the casting. This means that the fluid that has leaked past the piston seal now presents an uncompressible obstacle in the path of the piston movement. Couple this with the air that inevitably also occupies some of the space and the rise in temperature caused during engine operation, and you get a situation where the air/fluid is exerting a "backforce" against the piston and causing it to retreat into the slave cylinder!
As a result this actually tends to give a slight rise in the fluid level at the master cylinder mitigated by the loss of fluid from the leak)and also results in a large increase in lever travel before the clutch will operate due to the increased distance the piston now has to travel before it actuates the pushrod.
So what does all this mean??
Well, on both my bikes I observed that the DOT 4 fluid became dark very rapidly during use and it appears that this is caused by seal material breakdown. Mechanical wear on the seal would normally be far too minimal to cause leakage at the early mileages we have all seen. However, having looked at the inside of the pistons / cylinders of my bikes I can also say that the machining of the sliding surfaces is not the best and has probably contributed to the early seal failure through "abnormal" wear.
On both bikes, after completing modifications (aftermarket seal on the '98 and aftermarket cylinder/piston assembly on the '01)I did not experience any problems and the replaced DOT 4 fluid did not darken by any appreciable amount over the period since.
It is therefore my opinion that the standard Ducati seals are of the wrong material grade and as a result they react chemically with the clutch fluid. I also believe that the machining of the parts has lacked quality of finish and maybe (?) dimensional tolerances have varied more than they should.
Certainly I regard the clutch slave cylinder as the first item to upgrade on any of the ST series, unless of course you have never experienced a problem.
Hope this post is of some use to all of you.”
From Mike Mullen:
“Ducati redesigned them several times, the last of which was in 2001. The slave on the GC is like the older design. Evoluzione sells aftermarket pistons with better seals. Just pop out your old piston with compressed air, clean the bore, and pop in the new one. I think their piston/seal kit is $15. I always replace the older slaves entirely with better ones that ease the clutch pull. Evoluzione also sells them (and I stock them). The best made are by STM (very pricey – over $200) and Yoyodyne (a little less pricey – @ $190).”
From LT Snyder:
“It says they are for the '99-2000 slave and I am on a different bike today, but I can look at the slave when I get home. I'm not familiar with the difference. I replaced mine when it stopped working smoothly. I opened it to find scoring on the walls from the piston getting cockeyed in the bore. This occurs when the single o-ring seal on the piston flattens out. The new piston has two parallel o-rings and prevents this from happening.”
Another good source of information: http://www.moto-one.com.au/performance/clutch_slave_cyl.html
Rear engine bolt
The rear engine bolt has been known to stress and fatigue over time and if not checked can shear or lead to engine case cracking, both with dire consequences.
Some early warning may be gained if the torque is checked regularly (at every service). If the bolt has lost torque then it could be a sign that it has fatigued.
From 2001 onwards, Ducati has increased the bolt size from 10mm to 12mm. Time is yet to tell whether this has solved the problem.
As far as replacements go, Nichol's Manufacturing sell strengthened replacement bolts at http://nicholsmfg.com/. (Other sources?)
Helpful solutions: · Replacement bolts: http://nicholsmfg.com/.Thanks to Duncan Sargeant for the above piece.
Clutch Groan
From Mark Trbojevic:
“It's the sound of the clutch plates slipping over each other. I believe that blowing out the dust will help. Used to happen a lot with my stock clutch on the ST4s, usually when accelerating away hard from a stop!”
For a more in-depth look at the clutch see http://www.ducati-upnorth.com/tech/clutch2.php from Larry Kelly of San Diego CA (aka Shazaam!).
Clutch Wear
It would appear that every STx ships with clutch plates which have soft "tangs" which quickly wear away at the basket. This picture clearly illustrates the wear at the leading edge of the tangs: 
As the tangs wear, it creates greater freeplay and will damage the basket too!
Solutions include the Nichols light clutch basket in combination with Barnett clutch plates, or the Dr. Desmo quiet clutch kit. (confirmation? Any other product?)
(Thanks to Duncan Sargeant for the above info)
Fogging Headlight
Quite common on Ducati’s built from 1997 to 1999. The headlight looks as though there is a fine mist of condensation on the inside of the glass. Fixed under warranty in all recorded cases.
Loose alternator nut
A loose alternator nut doesn’t sound like a big deal, but here’s some information assembled by one of the listers:
“My 2000 ST4 had 18k trouble free miles until an alternator nut backed itself off, toasting the clutch (they are not directly connected, but the vibrations that occur damage the clutch). Apparently, Ducati dealers have not been notified that this nut should be torqued to spec during service. The mechanic that currently has mine, while I await a clutch basket from Italy, has been given Loctite for the nut. According to him the factory assembly directions called for the nut to be torqued after oiling! Anyway, I would STRONGLY suggest that you have this torqued and Loctited during your 6K service.”
A couple of responses indicated that their dealer has checked the nut as a routine part of each service. Now you know!
Chain Tensioner Warning
A couple of warning have been provided by owners regarding chain tension. You’ve been warned!
(From Ian Ellis)
The chain tension sticker was incorrect on some early models. Instructions were to adjust chain slack on the sidestand. New bikes have same style sticker but with the word centerstand instead.
The sticker on swingarm is not centred, so measurement at the arrow on the sticker will yield a too loose chain. Measure from centre of axle to centre of countershaft and make a mark half way in between.
(From David Harvey, UK) Ducatis such as the Monster, 851 and the ST series with the bronze-coloured end plates on the rear of the swinging-arm are prone to the cracking of those end plates, usually as a result of over-tightening of the chain-adjuster bolts. This type of chain-tensioning system leaves a lot to be desired from an engineering point of view. The nearside adjuster is particularly prone to loosening off, presumably due to some sort of torque-reaction from the chain and sprocket under acceleration. Using the bike over rough-roads and/or failing to sufficiently tighten the spindle nuts probably doesn’t help. To compensate, the adjuster bolts are often over-tightened, causing the cracking.
The standard adjuster bolts also require some form of security to stop them falling right out if they become slack and the Factory have fitted a small socket cap and washer to the other end. On my own ST2 I once found the near-side adjuster bolt had worked loose and when I fully withdrew it, the securing cap screw had also worked loose and fallen off inside the swinging arm!
One solution is to always torque down the fasteners whenever they are disturbed and then lock-wire them. My ST2 has been modified by Brancato Engineering in Oxfordshire (tel: 0865 891203) with what I believe to be a much better solution: He replaces the adjuster bolts with stainless steel studs which are secured into the spindle blocks with roll pins. The end plates are then secured with a stainless steel nyloc nut and washer. Problem solved with the advantage that when adjusting the chain, rear wheel alignment be checked accurately by measuring the length of studding protruding from the end plate.
Fuel Pump Relay
If you ever suffer from the “nothing happens when I push the starter” one of the problems might be the fuel pump relay. To diagnose the problem, turn the key to the on position, and you should be able to hear the fuel pump working. If you can’t, then the problem is either in the fuel pump relay or it’s wiring.
If the fuel pump is working, check the side stand cutout relay, or even the ignition kill switch.
Counter shaft sprocket retainer clip
If you ever suffer from the “nothing happens when I push the starter” one of the problems might be the fuel pump relay. To diagnose the problem, turn the key to the on position, and you should be able to hear the fuel pump working. If you can’t, then the problem is either in the fuel pump relay or it’s wiring.
If the fuel pump is working, check the side stand cutout relay, or even the ignition kill switch.
Counter shaft sprocket retainer clip
Listed as one of the recall items, the following friendly advice comes from a lister:
“Check the counter shaft sprocket retainer clip. I believe they started hardening these in 2000 and if yours goes it can strip the spline shaft which is an enormously expensive proposition. The clip is only ~10 bucks so its well worth getting a new one that you know has been properly hardened.”
Further detailed information has been provided by Justin:
“Remember, my ST is a '97, one of the first, and I had many failures of this clip before the recall for the replacement hardened black ones was issued. The dealer got to know me quite well, and simply installed a new retainer every time I rode into the workshop. All my failures were with the old 'gold' coloured plates. I have not had a single failure with the new 'black' hardened plates.'
The countershaft splines actually taper off before they go through the engine cases - they must do this to provide an uninterrupted surface for the oil seal around the countershaft, so theoretically it's impossible for the countershaft sprocket to run against the engine cases, as the spline doesn't go in far enough. When my retainer plate failed completely, the chain jumped the guide on the swingarm, and started rubbing against the inside edge of the clutch slave. There was NO damage to either the chain, or the swingarm, but slight wear marks on the nylon guide on top of the swingarm.
I didn't even know it had happened until I stopped for a break somewhere on the road, and something 'not quite right' caught my eye. Luckily I carried a spare retainer plate with me - even at that early stage it was a known weak point, and I simply replaced it with my spare.
I've only just replaced this clutch slave nearly 3.5 years later, and not because it failed either. I replaced the clutch slave just to get the easier clutch lever pull of late models.
If I were you, I wouldn't be worried about the new 'black' hardened retainer plates, as long as your chain is correctly tensioned, and has no 'tight' spots.”
Help! My bike won’t start!
It happens. You know, get the gear on, staddle the Duck, thumb the starter….. thumb the starter…. Third time lucky…. Nope – no go. If you’re lucky, you haven’t been left stranded. If you’re really lucky, maybe the answer is here.
Consider the following story from Ian Deary (00 ST2, UK):
“Saturday and Sunday were sunny in my part of the UK, perfect for a blast down some twisty lanes. At least it would have been if my ST2 had started! I’m baffled: The immobiliser beeps merrily (META 357) and the headlight, Neutral light etc. all light up. The sound of the fuel pump whirrs into life but it’s as though someone has disconnected the starter button. I’ve checked the kill switch, side stand position, followed the wiring from the starter for loose connections etc. - Nothing. Could it be a fuse or something else? It’s still under warranty but I may have to wait for at least a week before some bloke in a van comes to whisk it away.”
Connection problems?
A tip from John Stockwell (Takka):
“Check the main wiring connector on the L/H side, just by the fuse box, rectangular shape. Disconnect battery earth then part connector spray with CRC or similar or use some dialectic grease. These have been known to give trouble if moisture gets in. Check also the starter relay & connection on Starter solenoid.”
From Rog:
“I had a similar problem and popping the side stand up and down a few times cured it. I think the internal microswitch in the stand is suspect but it hasn’t happened again. Hope this helps. That sidestand kill switch is a real pain anyway don’t you find?"
Another tip: The little white relay connection (from the starter switch) is very easy to knock loose.
Starter doesn’t come on?
From Mike Mullen: “This happened to my bike during the first 100 miles of ownership. Low amperage wires to the solenoid weren't plugged in all the way. Another list member said that exact same thing had happened with his bike.”
Jump starting your ST
Ian provides a couple of options on jump starting your ST without having to strip the whole thing down. Note his disclaimer on Option 2.
“I found that the bike could be jump started without removing all the plastic.
Option 1 (TESTED) I removed the lower right fairing panel so I could get to the ground terminal, although in a rush you could clip onto the cable end that mounts to the rear of the engine case. I then went in through the front right air scoop to the starter solenoid by clipping onto the upper solenoid you can then fire the starter with the switch. I use mini jumper cables that I made to attach to the solenoid bolt. They fit nicely through the little opening in the fairing. They are similar to the ones that the bike catalogs have.
Option 2 (NOT TESTED and not recommended) - take a BMW accessory fitting and hook up long wires and small jumper clips to it. Then leave the bike connected to someone's donor vehicle for an hour or so and then restart it. That would take about the same time as removing and reinstalling the plastic. If you try it without allowing the time for their car battery to bring up the voltage in your battery the sudden inrush will blow the 3A fuse instantly (my guess). I currently have a 7.5 in there for an emergency tire pump that I carry, so I might be able to get away with it, but I'd be a litttle nervous about turning the wires into resistant heaters. Take a look at the small size of wire on the stock outlet and consider trying to jump start with them, you'll probably choose another method, like I did.”
Sluggish Starting
Many owners complain of their bike barely having enough energy from the battery to kick the bike over before it starts. The causes are twofold: The standard battery (for various reasons) sometimes loses some of it’s charge. Some owners will keep their bike on a battery tender to keep it charged, and thus minimise the starting problems. The later model (2001) bikes are fitted with a new maintenance free battery, which seems to be a little better.
The other main reason for sluggish starting is linked to the wiring which is connected to the battery. The standard wiring, while able to do the job, can be replaced with heavier (=thicker) cables.
Remember the formula V=IR where “V”= Voltage, “I” = Current and “R” = “Resistance”? John Swiatek sums up the theory very well:
“Normally higher resistance would decrease current, V=IR. R goes up, V stays the same, I must go down
However, when there is a motor in the circuit it will attempt to draw current until it has enough power to do its job; in this case it must turn the engine over. Due to the higher voltage drop in the smaller wire (V=IR) there will be less voltage at the starter motor terminals so it will draw more current (P=VI).
The battery must supply this additional current. So where does the extra battery power go? It is lost in the form of heat in the smaller wire (IsquaredR loss).
This is why transmission lines use high voltage low current to distribute power, it minimises I-squared-R loss. But since we are stuck with relatively low voltage we need "big, fat wires". :^)”
From Richard Strysniewicz after performing his own starter wire upgrade:
“Great advice, this came up a while back on the list and a few weeks ago I got around to putting new wires on my ST2. Starts much better now, well worth the hour or two invested. Used 4ga marine wire, tinned lugs, marine heat shrink, and some rubber caps to cover the positive connections. It was a bit fussy to get the 4ga routed but it worked.
That might be overkill and 6ga may work well and allow more flexibility. When you shop think 6 lugs - 2 each for cables from better to ground, battery to solenoid, and solenoid to starter.
Anybody try 6ga with success? I think someone mentioned that last time this came up. Stock appeared to be 8ga to me but I'm not positive as there were no markings on the wires.”
Helpful solutions:
o Check out the upgraded starter cable kit at http://www.jastek7.com
o Consider installing a Headlight-Gizmo from http://www.bike-gizmos.com
916 Rocker arm wear
There have been a few cases reported of rocker arms on 916 engines wearing prematurely. Essentially, the hardening on the arms wears or peels off all together. This is not an overly common problem, but happens occasionally, and seems to be an acknowledged fault - usually fixed under warranty.
That annoying rattle
Ian Ellis finally found the source of the annoying rattle on his bike, and shares his fix:
“I had been tying to find a rattle that primarily showed up on turns. It turned out to be the shaft between the gear shift pedal and the shifter spline. I put a nylon washer on either side of the rod and did up the nylocks to the point where they grip and it looks like I can listen to the engine without hearing that ugly rattle.”
Spongy brake lever
In most cases the feel of a spongy or imprecise movement on the front brake lever is cause by some air in the braking system. The usual solution is to bleed the brakes to remove as much air as possible. What if you’ve bled the system, and you still have sponginess? One option is to remove the pads, and push the brake pistons back into the calipers - this puts pressure into the system and helps remove some of the bubbles.
John gives us another simple, but innovative solution:
“What to do about this front brake? Then I remembered an old friend who could never get his brake to firm up on his GSX750. His solution (as told to him by A-grade racer, Wayne Clarke) - cable tie the lever to the grip and leave it over night. I did that very thing and the next day the sun is shining and I've now got a very firm front brake!
Why did this work - the pressure in the system over night slowly pushed the air bubbles I couldn't get out via bleeding up to the reservoir, the same effect as shoving the pistons back into the calipers, except I didn't have to take the calipers off.”
Front brake lever hits the fairing
For obvious reasons, having the front brake applied when you don’t intend for it to happen is not desirable (ask Dan if you need to be convinced!). The reasons could vary, from the installation of non-ST standard adjustable levers, to an accident which moves the fairing closer to the bike by a tiny amount.
Justin provides some information which might help:
“I don't know if you know, but all Duke's have screw and locknut adjustable steering stops down on the bottom triple clamp. You can stop your brake lever from hitting the fairing by adjusting the stop slightly - minimal impact to the available steering lock. I think, from memory you need a 10mm spanner and a 4mm or 5mm allen key to do it. No fairing panels need to be removed - you can reach down from in front of the petrol tank to do it.”
Lack of freeplay in front brake lever
While not unique to ST’s, or even Ducatis, this problem is worth mentioning. The symptoms include very little freeplay, or a feeling that the brakes are on, even though you are not touching the lever.
Richard has experienced this, and has responded to a list member who described the symptoms of a very scary ride home:
“Your dealer did not leave enough free play in the assembly. I did this to myself once on the 907ie I had before the ST2. Same type of adjustment on the front brake.
If there is not enough free play then the piston in the master cylinder does not retract enough to let fluid flow back into the reservoir. So you apply the brake, the fluid heats up and expands, but cannot return to the reservoir so it applies pressure to the brake pads, which heats the fluid more, and well you get the picture.
You do not want to adjust the screw in until it is tight, that will most likely result in too little free play. The screw should have a little spring thingy and a detent such that it locks every 1/2 turn. Does not need to be tight, the spring and detents will keep it in place (or at least mine have.)
How much free play is enough? Hard to say. Just be careful for a while any time you reduce the free play, do some hard braking in a deserted area to make sure there are no problems.”
Battery light comes on intermittently
This could be caused by a number of thing, most likely to be the regulator if you are riding an earlier model (98) ST2. If you’ve eliminated the regulator, try the tip is provided by Alain:
“I had that problem one time. I disconnected the two plugs between the alternator and the regulator (one is under the air box, the other one near the radiator cap). I put some WD 40 in there and, connected again firmly. No problem now.”
Temperature Problems
Temperature problems are amongst the most common enquiries by the members of the ST owners list. Many new owners feel as though they may have a temperature problem when they first notice that the temperature climbs up above 212 F or 100 C on a warm day. As explained in section 4.10, these observations are normal for these bikes. If you temperatures are consistently high, don’t drop once mobile, or are way above those listed in the owners manual, then get your bike checked. The manual for my 2001 ST2 indicates that the maximum temperature is 120C (248F). If this temperature is exceeded, then the temperature indicator will start blinking.
Occasionally though, there is a real temperature problem, with the temps rising far above what is considered acceptable.
Here are some tips if your engine is overheating:
- Check to see if both sides of the radiator are the same temp, by hand on side tanks. If not then you have a circulation prob.
- Make sure that the small tube from fill up/header tank isn't kinked (Takka).
Rear Brake Line warning
A potential problem with the rear brake line wearing through on an ST2 was reported by Ray C:
“I have just noted an interesting and potentially serious problem with the rear brake hose "carrier" on my ST2. I'm not aware that anyone has ever mentioned this before, so maybe my bike is an isolated case, but here are the details for your information:
On the ST2 there is a wire "carrier" above the swing arm which holds the rear brake hose out of harms way. It is presumably designed to prevent the free length of hose from becoming abraded or trapped by the rear suspension spring and associated mechanicals.
I have noticed that the wire carrier is actually damaging the hose quite severely. In my case the hose has a chunk of rubber missing from its wall because the end of the wire has been digging into it during the natural movement of the swingarm.
Although the hose has not failed and I have since "modified" the carrier slightly, there is a great potential here for unexpected failure of the rear brake.
I would advise all ST owners to check the carrier on their bikes to make sure they do not have a similar problem.
My Ducati dealer has put in a warranty claim and they will be replacing the hose, but it doesn't sound like Ducati are planning on changing or modifying the wire carrier.
As a temporary measure I have fitted a piece of thin rubber sleeving over the wire end and also bent the wire end outwards slightly to help prevent further damage to the hose.”
Spluttering and Stalling
One owner reported a problem whereby his bike would misfire, splutter and sometime stall. Stephen provides a suggestion:
"...since the onset of colder weather here in the land of Oz. I have been putting up with the her spluttering sessions for the last couple of weeks and will do so until she goes in for the 50,000 km service. Feels like it is electrical in nature. Maybe a regulator on it's way out. It usually does not happen until I have done at least 20 km and then she will splutter and misfire and sometimes almost die.
It was one of the temp sensors that was intermittently going bad.
The Mathesis should pick up that straight away, my extended episode with it was due to my mechanic/dealer not having a Mathesis. Once I had it diagnosed on the Mathesis it was obvious. Check the connections to the sensors first, they may just need some attention.”
Cylinder base gasket leak
A few instances of the gasket at the base of the rear cylinder leaking have been reported. Fariborz did some research:
“After all the posts about the leak, I decided to call Munroe Motors to find out why the gasket leaks and what is the solution. This is what the service guy, Rick, at Munroe said:
Ducati has changed oil passage ways on the vertical cylinder for better lubrication on the 2001 and 2002, 4 valve 916 engines (Monster S4 and ST4). As part of this modification, the gasket was also redesigned to accomodate the changes.
Anyway the new gasket design leaks on some new bikes (Do not know how many). The solution is to remove the cylinder and put what they call gasket goop for lack of better term, and let it dry for overnight.
According to Rick at Munroe, this is a two-day or three-day job (need to let the goop dry out). No drilling of any kind is required.
The good question is why did Ducati Modified the oil Passage way to the vertical cylinder for better lubrication! You do not think it has to do anything with the FLAKY ROCKER problem, do you? Noooo. ~8O)”
After reading the information supplied above, Jason did some further research:
“Ok, after reading this I decided it was time to call Moto Britalia and find out exactly what they were talking about. I spoke with the head mechanic there who said they've seen this problem on many of the 916 engines. He said that what they do is pull the cylinder, put a bolt in the oil passage that goes into the rear cylinder. He said that excess pressure is caused by the way that the oil is being pumped into the cylinder for the 4-valves and having nowhere to go causes the gasket to leak. By putting a bolt in the oil passage it reduces the volume and pressure while still supplying the appropriate amount of oil to the valves.
I did ask them if the problem had reoccurred on any of the bikes that they had made this repair on and their answer was "not a single one." Not that I expected any other response, but he seemed quite emphatic when making the statement. This explanation along with $1.50 will get me a cup of coffee...I have no freaking clue what he's talking about!! So, does this make any sense to any of you?”
If, after reading all of this, you are still not sure what to do - ask the list or check with a dealer yourself!
Exhaust popping and/or occasional backfire
Quite often owners will experience an occasional popping sound on deceleration, and the bike may occasionally backfire. This info from Warren might help:
"After putting pipes and a FIM chip on my ST2 popped and farted on deceleration and also popped at a steady rpm without a lot of load around the 4500 -5500 range, it would even backfire sometimes at this rpm. I put up with all this for some time until there was some info on this list saying that the more open pipes tended to allow the engine to run a little lean and that a tweak of the trim pot inside the cpu was in order. The trim pot is located under the sticker and then under the rubber bung on the cpu.
You need a trimmer screw-driver as these are meant for this job and are fully insulated. Carefully turn the pot which is next to the chip counter clock wise for richer. Turn till it stops but do not force then back about half way from where you started. The trim pot does not do a full turn and the standard position is in the middle. If it still does it go richer again. After I did this to my bike the popping and the backfire has disappeared and the engine runs much smoother.
Hope this helps. I would try this first before doing the chip as it might save you some money.”
Bike runs poorly, won’t rev over about 5000 rpm
The following eui (extremely useful information) comes from John Clifton. Sounds like he found out the hard way.
“Numerous ST owning friends of mine have had this problem occur, usually after a service where the fuel filter has been replaced:
Symptom - bike runs very poorly, refusing to rev over about 5000rpm.
Cause - one of the fuel lines in the tank attached to the fuel pump has come adrift, usually due the pipe not being reattached properly after having the fuel filter changed during a service
Remedy - remove tank, lay upside on ground (hopefully on something soft, say your pillion's jacket - they can put up with the petrol fumes..), remove fuel pump from tank, be careful as the seal can make it a bit of a struggle, re-attach offending hose, stop, now recheck the hoses to make sure they are all going to the right outlets, replace the o-ring seal with that spare one you carry under the seat, grease the o-ring with a little chain lube, carefully put the pump back in the tank, tank back on bike etc.
Ride away cursing the useless mechanic who failed to attach the hoses properly in the first place.”
Rusty Steering Head Bearings
Some owners have reported that Ducati is pretty lousy when it comes to putting gread on the steering head bearings, resulting in some noticeable rusting.
Dave Harhay:
“I just finished inspecting the 03ST4s steering head bearings. Like everyone says… there's not a lot of grease on them. FYI there is a seal, so the chance of water and crud getting into the bearings is small. I am not sure of the other models however. I put in a liberal amount and retorqued the special nut.”
From Ron Ginter:
“I've got rusty steering head bearings!
They will be replaced under warranty (phew!), but I wondered if anyone has had a similar experience? My dealer says that Ducati doesn't grease them very well because they don't consider that we'll ride their touring bike in the rain <g>, so I immediately wondered if anyone in the soggy Pacific Northwest has had this problem?”
From d888spoltd:
”Sadly, your dealer is correct. I don't think that's any different than many other manufacturers however. Check out this months RoadRacing World for a commentary on bearings and lubricating them. I took apart wheels, steering head, and swingarm pivot on both my Ducatis when I bought them and each were fairly starved of grease. It never hurts to take them apart, clean and regrease.”
Bill Anderson says:
”I posted the rusted steering head bearings question on the UK ST Yahoo site because of the similar climates of the UK and PNW. I got an e-mail from a gentleman in Northern Ireland who replaced his at 35,000 miles because of rust.”
From Darren George:
“Mine were stuffed at 20 thousand km, I was not happy, the boys told me they HAVE to be re-packed at 1000km`s or they rust, as apparently they go sparingly with the grease at the factory… dear [expensive[ little buggers too!! Now I re-grease them every 10 thou or so.”
“I was told at the local dealership, they do their own things as well as factory procedure, and they’ve found in the past that the head bearings need re-packing at the first 1000km service, so that they last at all....and having to replace mine @20,000, I’m not going to argue, as apparently they mustn’t have been packed… maybe it’s more like a ‘grease top-up’, more than an actual re-pack.”
Sandy Thompson:
”My 2002 ST4s had rusty lower steering bearings at about 4000 mostly sunny miles.”
From Robert Mohns
”Over the past few months, I'd noticed that the bike wasn't handling quite right. I wasn't sure even how to describe it, but when I was in a couple weeks ago to have a new front tire put on, Eric gave it a test ride and said that he thought the steering head bearings were in bad shape – "dry", he described it. So he pulled them out, and sure enough, they were not happy campers – brown sludge. The upper "seal" doesn't really fit closely enough to seal, so water and dirt can leak in. The bottom is sealed fairly well, though – so water and dirt get in and mix with the grease around the bearings, resulting in the bearings moving in what looks and feels just like mud! The upper bearings weren't nearly as bad, but weren't good either. Two new bearings were $48 each, and the bike handles like it's supposed to again!
If, like me, you ride your bike in the rain, you might want to consider checking and if necessary replacing the bearings as your mileage mounts”
