lowside Posted June 5, 2023 Report Share Posted June 5, 2023 Hi all, I'm gradually working my way through maintenance items on my "new to me" bike. I've noticed that in 1st gear there is sufficient clutch drag to pull the bike forwards unless I am sitting on it. No noticeable drag in 2nd gear. Also, it is almost impossible to find neutral if the bike is running, although it can be done by hand, with limited success. I believe it is a diaphragm type clutch. It has recently had new levers (for cosmetic reasons), but I've checked the play in those and the master cylinder is operating with a full cycle. Just to be sure, I misadjusted the lever to remove play entirely and the result was the same, so I think the actuator rod is fully engaging and disengaging the piston in the master cylinder. I've dropped the oil, which was somewhat dirty but not horrific. There was a tiny bit of swarf on the drain plug magnet. It's had 650cc of fresh 75W (GP10) put in, bringing it up to full as far as I can tell (I think its ~700cc total capacity). I am wondering if the clutch needs a little more fluid in the line? I've noticed the brake lever engages very early in the stroke, which suggests to me, assuming I've adjusted the lever correctly, that it has potentially too much fluid. Worth checking both in case they have been filled incorrectly? It's all DOT4 if that makes a difference to anything. I am not experienced with motorbike mechanics, so I was hoping someone may be able to point me in the direction of things I should check for the clutch drag issue? If necessary, I'm willing to put in a new clutch kit, but obviously want to rule out simple stuff first as taking the clutch apart, for me, would be a challenge. Thanks Quote Link to comment Share on other sites More sharing options...
cascao Posted June 6, 2023 Report Share Posted June 6, 2023 Clutch drag can be less with engine hot. Your clutch drag is when hot? You can try other oils to bring clutch to your style. Not finding neutral when bike moving is a good thing....and safe. Be carefull some clutch hydraulics use mineral oil not dot fluid An little grey fine like sand swarf is ok The amount of oil in master cylinder doesn't change disengaging point. It has to be above minimum. 2 Quote Link to comment Share on other sites More sharing options...
lowside Posted June 6, 2023 Author Report Share Posted June 6, 2023 19 hours ago, cascao said: Clutch drag can be less with engine hot. Your clutch drag is when hot? You can try other oils to bring clutch to your style. Not finding neutral when bike moving is a good thing....and safe. Be carefull some clutch hydraulics use mineral oil not dot fluid An little grey fine like sand swarf is ok The amount of oil in master cylinder doesn't change disengaging point. It has to be above minimum. Hi cascao, Yes it seems to drag most of the time. I've been out today and had a couple of problems, but as I don't really ride in 1st, I'm not sure how much effort to put into fixing it, but it can't be good for clutch temps or wear. Neutral can't be found when the engine is running usually. Only with the engine off and even then, I typically have to use my hand. Again, not a major issue, just would like to sort it if I can. Thanks for note about master cylinder, I will check when I wash it. Thank you Quote Link to comment Share on other sites More sharing options...
feetupfun Posted June 7, 2023 Report Share Posted June 7, 2023 12 hours ago, lowside said: Hi cascao, Yes it seems to drag most of the time. I've been out today and had a couple of problems, but as I don't really ride in 1st, I'm not sure how much effort to put into fixing it, but it can't be good for clutch temps or wear. Neutral can't be found when the engine is running usually. Only with the engine off and even then, I typically have to use my hand. Again, not a major issue, just would like to sort it if I can. Thanks for note about master cylinder, I will check when I wash it. Thank you It's a fairly normal thing to shift to neutral before you come to rest if you want to then sit in neutral with the motor running. It will shift easily to neutral if you shift when there is no torque on the gearbox (ie motor not driving bike or bike not driving motor). It is quite normal for shifting to neutral to be difficult with bike stopped and motor running (clutch drag puts torque on the gearbox). 1 Quote Link to comment Share on other sites More sharing options...
lowside Posted June 7, 2023 Author Report Share Posted June 7, 2023 14 hours ago, feetupfun said: It's a fairly normal thing to shift to neutral before you come to rest if you want to then sit in neutral with the motor running. It will shift easily to neutral if you shift when there is no torque on the gearbox (ie motor not driving bike or bike not driving motor). It is quite normal for shifting to neutral to be difficult with bike stopped and motor running (clutch drag puts torque on the gearbox). Thanks feetupfun, I'll give that a bash then, see if I can find neutral when its moving as I haven't tried that approach. 1 Quote Link to comment Share on other sites More sharing options...
cascao Posted July 7, 2023 Report Share Posted July 7, 2023 Release clutch lever position bolt to reposition clutch lever away from handlebar. Re adjust freeplay. In this way you will have more stroke....can be a solution. 1 Quote Link to comment Share on other sites More sharing options...
lemur Posted July 7, 2023 Report Share Posted July 7, 2023 On 6/5/2023 at 7:35 PM, lowside said: ...t. It's had 650cc of fresh 75W (GP10) put in, bringing it up to full as far as I can tell (I think its ~700cc total capacity). ... Service manual calls for 580 ml ATF type which is way lower viscosity then 75W gear oil. <- might want to check that. I would expect to see some clutch drag in any motorcycle if the viscosity is very high (75W) and oil level is above normal. ATF is way closer to the ISO46 hydraulic oil that I run with viscosity ratings closer to 20W relative to engine oil. If only one gear range drags I would be looking for a problem on the gear itself or the shift mechanism associated with it rather than the clutch which will affect all of the gear ranges. 2022 model certainly should not be experiencing gear problems if it was assembled correctly at the factory. The motivation for using DOT fluid in brakes is in the event you have a brake system leakage then you will be spilling ethyl glycol on your brakes instead of oil. If your clutch hydraulics leak they leak outside or into your transmission oil so it is far more logical to use oil in a clutch hydraulics. The hydraulic fluid needs to be compatible with what you use for hardware, but for the mot part DOT brake fluid is more problematic when it comes to corrosion and water absorption. (most DOT fluid is hygroscopic in nature, it absorbs water from the atmosphere, water is not a problem with the thin mineral oil used in a clutch hydraulics. 1 Quote Link to comment Share on other sites More sharing options...
cascao Posted July 22, 2023 Report Share Posted July 22, 2023 Sherco ask for dexron 6 in these years. Way thinner than more common dexron 3... 1 Quote Link to comment Share on other sites More sharing options...
bikerpet Posted July 23, 2023 Report Share Posted July 23, 2023 First be sure the lever is setup well. I'd adjust the lever out as far as you can comfortably reach, then ensure there is a couple of mm of totally free play before the pin starts to push the piston to ensure the fluid can return properly. If there's still the same drag I'd be trying some different oils. If Sherco call for Dexron 6 as cascao says, then try that - the factories know their bikes. I have found Putoline N-tech Trans GP pretty good, but I'm sure Gro and all the other common trials oils are good too. Putoline GP10 has a low viscoisty index, so it's viscosity will vary a lot between hot and cold - ignore cold drag and make sure the bike is well warmed up before checking the drag. Your "swarf" comment is concerning. If it's superfine powder / smooth paste then it's fine, probably just wear from the clutch plates. If it's actually swarf that feels gritty or worse then there's a problem that needs fixing ASAP. On 7/7/2023 at 10:08 PM, lemur said: Service manual calls for 580 ml ATF type which is way lower viscosity then 75W gear oil. <- might want to check that. 75W gearbox oil is completely different from 75W engine oil. Why on earth they'd use the same rating numbers for a different rating system is beyond me! Setup to confuse people. GP10 75W oil has 100C viscosity of 5.5. Typical ATF Dexron 3 is around 7 - 7.5. So the GP10 is actually considerably lower viscosity than the ATF DIII. 2 Quote Link to comment Share on other sites More sharing options...
lowside Posted August 7, 2023 Author Report Share Posted August 7, 2023 The clutch lever is properly adjusted, first thing I checked. I will do some further testing. Dealers said GP10 is too thick for the Sherco and can cause the diaphragm to swell? Problem is, as it was a used bike, I've no idea what was used previously. Thats the next thing I'll look at if I cant solve this with just gearbox oil. The swarf wasn't anything that made me cringe, I just dont think the oil had been dropped for a while and the engine probably hasn't seen that much use. When I come to change it again, if theres still a bit of swarf, I think it would be worth digging into deeper. It's fines, not chunks. Does anyone have a late model Sherco 250, what do you run in yours? Quote Link to comment Share on other sites More sharing options...
lemur Posted August 7, 2023 Report Share Posted August 7, 2023 Is it still dragging in first gear only and no clutch dragging in second or third gear? Quote Link to comment Share on other sites More sharing options...
lowside Posted August 7, 2023 Author Report Share Posted August 7, 2023 9 minutes ago, lemur said: Is it still dragging in first gear only and no clutch dragging in second or third gear? Haven't ridden it since my last post as we've been away a lot so nothing will have changed. I'll be riding it soon and you guys have given me some info to go on. I need to make more detailed records of what happens and when. I'll post back. Thanks 1 Quote Link to comment Share on other sites More sharing options...
lemur Posted August 7, 2023 Report Share Posted August 7, 2023 I just checked the price of the transmission oil you are using compared to what I use, says you pay about $24 per litre and I pay $8.10 per litre. That's sick. What's the nearest farm tractor dealer to you? Buy what they run in the hydraulics and transmissions of their big expensive equipment, change it frequently, it will work. ... do not over-fill, that won't work. Quote Link to comment Share on other sites More sharing options...
lowside Posted August 7, 2023 Author Report Share Posted August 7, 2023 1 minute ago, lemur said: I just checked the price of the transmission oil you are using compared to what I use, says you pay about $24 per litre and I pay $8.10 per litre. That's sick. What's the nearest farm tractor dealer to you? Buy what they run in the hydraulics and transmissions of their big expensive equipment, change it frequently, it will work. ... do not over-fill, that won't work. Putoline (anything) is expensive stuff, but running costs for trials aren't really too bad overall. Nano Trans is even more expensive, roughly double the cost of GP10! Some of it is marketing, thats for sure, but there are differences in products that aren't immediately obvious, so when you venture outside manufacturer specs, it's at your own expense. I don't know enough to be particularly bold. Quote Link to comment Share on other sites More sharing options...
lemur Posted August 8, 2023 Report Share Posted August 8, 2023 When you have a small volume of oil that has no filtration or water separator, the logical best practice would be to change the oil out frequently. The transmission oil I have been using successfully for decades in dozens of different engines costs about 5 bucks to change and it works great in winter or summer. Suit yourself but no transmission oil that should be changed frequently is worth 24$ per litre, you're paying outrageous money for packaging. If you want to know what is in a packaged chemical product the best place to start is the MSDS (Material Safety Data Sheet) it's the only place they are compelled to be 100% truthful about what they are selling you. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.