Hi guys, I have a St1300 with 35k miles on it which I bought used a year ago. While riding there was a grinding sound and the clutch felt wrong. I opened her up and sure enough one of the friction disks had all but completely disintegrated. I also noticed after towing it home that the oil level was bellow the sight glass so that I could see no oil. A non trivial amount of oil did come out when I drained it though, I probably should have measured. I saw no leaks, the coolant was clean, and I had checked the oil 2 weeks ago and it was full. Would the clutch problem have caused the oil level to recede, or did the oil level drop and cause the clutch to fail? Why would a clutch explode like this? I'm going to drop the oil pan and get all that crap out of there but I wounder if there is a deeper problem. I have attached pictures, it seems like the friction disk fused to the steel plate before exploding. If you have any Insight I would be grateful.
Clutch Friction Disk Disintegrated, Why?
- Thread starter ILikeBigBikesMan
- Start date
The friction fiber disk probably fractured due to it welding onto the steel plate. The fact that it welded onto the steel plate is simply caused from excessive heat. Oil level could certainly cause the clutch to heat up. I've never seen this type of failure on a ST before. I know Police bikes are known to have clutch issues due to heavy clutch usage around town etc.. I would look carefully at the clutch hub center bearing as low oil could damage the bearing. Also the clutch springs can lose tension if overheated so consider new clutch springs. The question of where the oil went needs to be answered.
How could you lose a quart or more of oil and not notice it on the floor of your garage or under your parked bike? I think the oil has been gone for more than those 2 weeks and you mistakenly saw a good level in the sight glass.
woodybelle
Site Supporter
The oil level is extremely sensitive to the angle of the bike. I have thought that my bike was level and added oil only to find out that I over filled it. These bikes usually do not use oil so if you had a full crankcase in the recent past it is probably just put up on the center stand in a slightly different angle. I check my oil in the same spot in my garage every time to avoid mistakes.
Couple of causes for Clutch lining to come off it's steel disc, water/coolant. In your oil,( normally in a Cage when the Rad intercooler for the transmission fails) . Parking the bike for a long time, lining tends to bond to the steel disc, so when you go to ride you have to break it loose , which eventually the glue will let go. "Hint sip tie the Clutch lever in the release position". Slipping the clutch excessively, ( to much slow practice) , creates to much heat. Wrong kind of engine oil, ( no don't blame me for saying that) hopefully you using oil designed for wet clutch. Another thing that comes to mind, is bad glue from the factory ( bad stuff happens). On a high mileage bike excessive wear on the clutch hub and drum , can drag the disc and burn out the lining.
When you go to install your new clutch, soak the lining plates in engine oil over night. ( Very important) . Hope this helps you, G
When you go to install your new clutch, soak the lining plates in engine oil over night. ( Very important) . Hope this helps you, G
tnbill
Site Supporter
It looks more like the friction material delaminated not welded. Why is a good question. Moisture is one cause as the glue is water soluble. I would also replace all the friction plates at a minimum.
wjbertrand
Ventura Highway
Previous owner may have abused the bike or had no idea how to use the clutch. I’ve seen newbie and abusive riders ruin a new clutch in just a few hundred miles.
Not sure the oil level question is related but these bikes aren’t known for consuming or leaking oil. As others have said set the level of the oil with the bike on a flat surface using the centerstand. Then check the oil level over miles/times with the bike parked in the exact same place. If the oil level continues to drop, it may be another sign the bike has been abused.
Not sure the oil level question is related but these bikes aren’t known for consuming or leaking oil. As others have said set the level of the oil with the bike on a flat surface using the centerstand. Then check the oil level over miles/times with the bike parked in the exact same place. If the oil level continues to drop, it may be another sign the bike has been abused.
- Joined
- Nov 20, 2005
- Messages
- 462
- Location
- Cedar City, Utah
- Bike
- 12/04/AZ05 ST 1300s
- 2025 Miles
- 006261
I'm going to guess that someone did a lot of low speed maneuvering and got it nice and hot.
The cop bike that I pulled the engine out of had 74K miles on it, but I doubt if that was it's first clutch. And the clutch I pulled out of it was toasted pretty good!
The cop bike that I pulled the engine out of had 74K miles on it, but I doubt if that was it's first clutch. And the clutch I pulled out of it was toasted pretty good!
I had that happen on my VFR that sat for about 4 years . Clutch operation was great until all the friction material left the steel parts .
The gun gurus say never to leave cartridges in the magazine compressing the spring for long periods of time, lest the spring take a set and fail to feed the rounds reliably. A clutch is not the same thing, but I question the wisdom of collapsing the springs for long periods when the bike is in storage.
Looking at the components around the clutch it looks like it got warm so heat was a part of it, I wonder how good the clutch material was. I have also seen some additives cause the clutch material to deteriorate the clutch.
Not all the additive manufacturers are lubricant engineers, as tnbill said some of the glue is water based and moisture wrecks it. I have seen that on automatic trans clutch packs and additive packages that dissolves the glue.
Where the oil went is a question that needs to be addressed, I agree with the statement above. These bikes don't tend to burn oil and mistakes can be made, oil level low enough to burn the clutch would have done a whole bunch of damage before the clutch failed, I think. If you are in this deep pop the valve covers and take a look at the cam lobes.
As to wrong additives i will return to my mantra- some additives won't hurt your engine.
Not all the additive manufacturers are lubricant engineers, as tnbill said some of the glue is water based and moisture wrecks it. I have seen that on automatic trans clutch packs and additive packages that dissolves the glue.
Where the oil went is a question that needs to be addressed, I agree with the statement above. These bikes don't tend to burn oil and mistakes can be made, oil level low enough to burn the clutch would have done a whole bunch of damage before the clutch failed, I think. If you are in this deep pop the valve covers and take a look at the cam lobes.
As to wrong additives i will return to my mantra- some additives won't hurt your engine.
Good point, about springs setting, real answer is ride a bike often. Never Store it.
Hardest thing on a motor vehicle is sitting, engines that don't stop last the longest
Hmm. As it so happens I was doing low speed turns when my bike wailed is crunching sound of agony. Not much though, I sometimes do like 10 - 15 figure 8s in my parking lot at work and have done them before without issue. I would think that bikes like these would be built to withstand a lot of clutch use like this. I also have been riding my bike pretty consistently. I check the oil level on the center stand in my garage with is pretty level if not perfectly so. Also I did clean up what seemed like an unusual amount of oily grime from the clutch cover before opening it up, perhaps the gasket was failing? It's low mileage but up in years I suppose. I'll go ahead and replace all the friction disks (no way I'm not doing that now after having done all this work) and that one steel plate along with the springs as was suggested. I'll use this oil
https://www.amazon.com/dp/B00I87F5C0?ref=ppx_yo2ov_dt_b_fed_asin_title
And then check if the oil level lowers as I use it. It could be a bit, waiting for parts, going home for the Holidays, but I'll post the results here eventually. Thanks everyone.
https://www.amazon.com/dp/B00I87F5C0?ref=ppx_yo2ov_dt_b_fed_asin_title
And then check if the oil level lowers as I use it. It could be a bit, waiting for parts, going home for the Holidays, but I'll post the results here eventually. Thanks everyone.
Oh one other theory. A lot of oil came out of the clutch cover when I opened it, perhaps a good half quart. I don't think that is supposed to happen, it did not on one other bike I did a clutch on, what do you think? Perhaps the friction material clogged the passage of oil to the oil pan and that caused the oil to not reach the sight glass? This might be a bit optimistic. I did drain the oil before taking that thing off and I did not ride it much after the sound but I did limp it half a mile.
Magazines have been left loaded for many years, and never taken a set in spring length.
They found out that the working of the spring back and forth fatigued the spring more.
Check your clutch lever bushing.
The hole may be worn too deep and you’re not allowing the clutch to work correctly!
Also sounds like you have have lost your water pump oil/mechanical seal, if the front of your engine was that bad.
This could also allow coolant in with your oil.
The hole may be worn too deep and you’re not allowing the clutch to work correctly!
Also sounds like you have have lost your water pump oil/mechanical seal, if the front of your engine was that bad.
This could also allow coolant in with your oil.
Ok. I can check the clutch level bushing later on. As for the coolant at least it looked very clean when I drained it. I'm not an expert but the oil looked fine as well.
Sadlsor
Site Supporter
I routinely practice u-turns (like, a LOT), including using the friction zone, but I don't "stay" in the FZ all day long; my turns are pretty quick.
As a data point, my 2008 is still a toddler; not quite 30k miles yet, and obviously the original clutch.
Supposedly I'm an expert at Mechanics, okay rebuilt Automatic transmissions since I was 19. When oil gets contaminated with coolant it starts looking like a Chocolate milkshake.