Thumper Club Forum
Technical => Bike Problems/Questions => Topic started by: chippit on June 03, 2010, 06:10:48 PM
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Hi, I am finding it very difficult to get neutral when the bike is hot.
After 15 miles it will not come out of neutral unless you stop the engine. I am running on halfords semi-synthetic oil, and have got 3-4mm play on the clutch lever, is there any other adjustment? The bike has only done 9500 miles so it is not worn out and not slipping.
The down pipes are very blue, does this mean it is running hot.
Thanks Christine.
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Aye Christine,
Sorry to read of your tale of woe.
Are you running Halfords motorcycle semi-synthetic or car semi-synthetic?
Is the mixture 'weak'? Hence the blue pipes and 'hot' engine. Check for a blocked up air filter on the carb. Air leaks around the intake hoses between the carbs and the cylinder head or split intake hoses (spray with WD40 and watch for bubbles or change in exhaust note, also squeeze hoses).
Have you made any adjustment at the adjuster above the alternator casing (near/left-hand side of the motor afore adjusting at the clutch lever end of the cable?
Are you running with insufficient oil?
Can't think of anything else, suspect the Steve's, Andy or Ian maybe able to add guidance.
Hope this helps, Bill.
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Christine
What exhaust system are you running ?. Is it the original or aftermarket ?.
When you says Halfords semi-synthetic is that bike specific oil or general car oil ?
You say you are finding it difficult to get neutral and then say it wont come out of neutral unless you stop the engine was this a typo ?
Is the clutch predictable other than that ?. So when you are pulling away and slipping the clutch, is the bite point always the same ?.
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I am using halfords motorbike oil, the bike has the standard exhaust,
You can shift down the gears but once it is in 1st it will not click back into neutral or any other gear. I have been stopping the engine then getting it into neutral.
The clutch seems to be operating normally otherwise but I have noticed that starting from cold and engaging 1st it is making more of a clunk as it drops into gear.
Thanks Christine.
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Aye Christine,
MMMMMMMMMMMMMmmmmmmmmmmmmmmmmmmmm!
Sounds as though your clutch is not releasing when hot due to thermal expansion of the plates. Insufficient space between the plates.
Has the bike been standing for a while and once brought back into use, this problem started occuring?
If this is the case, the clutch plates could be 'gunged' up (technical term for getting stuck together!). To cure, remove the clutch outer cover. Dismantle clutch, by removing springs, pressure plate and all the clutch plates (keeping them in order!!!!). Leave the clutch basket in place.
Wash all components in thinners, petrol, or brake cleaner. Dry.
Measure all springs for overall length (are they all the same, variable, all within the maximum length tolerance?). Any variation or over tolerance length, even by 0.2mm, REPLACE the set.
Measure all the clutch plates for thickness (less than minimum thicknes, REPLACE). Check all clutch plates for warping by laying on a surface plate and trying to slide a 0.2mm feeler gauge between the surface plate and the clutch plate. If you can, REPLACE the clutch plate. If there are burrs on the tangs around the outer or inner edges of the clutch plates, remove with a fine file or oil stone.
Check there are burrs on the faces of the clutch basket or on the clutch inner, then these will need to be dressed.
The burrs are preventing the clutch plates from sliding freely when the clutch is engaged and released.
Flush everything with brake cleaner. Re-assemble in the correct order, use a new genuine Yamaha case gasket with a light smear of gasket sealer. Pattern gaskets can burst at the 10:00 o'clock position where the gasket mating surfaces are narrow. This releases copious quantities of hot oil all over the rear tyre!!!! ??? Had the slip-sliding away moments!!! ??? Very nasty and not recommended.
If you require a workshop manual, then I can supply pdf on CD.
Alternative problem, maybe ball bearing or pushrod from left hand side of engine to the right is worn. Hence insufficient movement, despite correct clearance at handlebar lever. Poor hardening of components! Not heard of this as a common fault, but have known the ball to wear after a high mileage and the end of the rod to become 'cupped'.
After that lot, not sure. ???
See if SteveH has any alternative ideas??????????????????????????
Regards, Bill.
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I'm with Bill you probabaly need to strip the clutch. Before that I would check that the lever can come right back to the bar, have you got really thick grips or a bar end mirror which could be stopping it ?. Also check the engine end of the clutch cable, the lever it fits into has a point on it, this is supposed to point to a 'pimple' on the casing, if not then you will have to take the casing off and adjust.
I'm a bit of a cheap skate, so in the past I have avoided draining the oil by taking the tank off and battery out and leaning the bike on its side, you can then get the clutch case off without too much mess. I also re-use gaskets, I use a thin feeler gauge to free them from the casing and then grease them when I put them back to stop them sticking. If I do replace a gasket its generally with a genuine one, they are not cheap but are a better fit.
The other thing to check when the casing is off, is for play in the back plate, try rotating the clutch housing and see if it moves relative to the gear mounted on the back of the clutch housing. Also whilst you are there check the primary drive gear, they are prone to working loose.
With the exhaust pipes blueing does the bike smell hot after a ride ?.
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Thanks for all the advise, I have adjusted the clutch cable at the casing end, it has been a bit better but still not as smooth as it was. When I start it up from cold there is quite a clunk as I put it into 1st, it never used to do that.
Is there a better oil that anyone can recommend, it is the halfords motor bike semi synthetic that I have been using.
Another question, when I took the exhaust system off there were no gaskets between the head and down pipes, I bought some off ebay but found they were too thick to be able to do the nuts back up. I put a standard system back on (thankyou srxer) but without the gaskets, it isn't blowing but could this be causing the down pipes to blue? I don't think the engine smells too hot after a run.
Regards Christine
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Aye Christine,
Unit construction singles are 'hard' on oil, as they give it a good heating and then 'chop' the molecules in the gearbox. However, modern oils even Halfrauds motorcycle semi-synthetic should be fine. Just change it regular (2000 miles) along with the filter. [Search previous 'threads'.] Still think your clutch plates could do with a rinse.
Reads as though you are fortunate for the pipes not to be 'blowing' at the exhaust ports, if you are running without gaskets. Just wondering if your exhaust ports are 'clagged' with old exhaust gaskets/GunGum if the gaskets won't seat, or are the new ones like feather pillows? Should be copper, with an asbestos core, which compresses to form a gas tight seal when you tighten up the nuts onto the exhaust flanges. Whilst there might not be any loud 'blowing', any leak could allow air into the exhaust system and an 'afterburner' effect upon any unburnt fuel, resulting in 'bluing' of the pipes. Less backpressure from the exhaust system, could result in less effective filling of the cylinder with fuel/air mixture and consequently weaker/hotter running. Just the same as taking the baffles out of the exhaust, but not increasing the jet sizes to put the fuel in, so as to keep the fuel:air ratio correct.
Regards, Bill.
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Christine,
Are you sure there isn't gasket, they are very good at blending into their surroundings making it look like there is nothing there.
As for oil I generally use Catrol GPS 10w40. What grade of oil are you using ?
Steve
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Hi...just had a similar problem but on a much smaller scale on the xbr.Had the clutch lever housing off a few times and seems to be tight or bend sharp at the headlight this bend relieved made a marked difference on the gear selection,1st and 2nd.Hope you find an answer soon.
Good luck,Pete.
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The halfords 'part synthetic oil' is 10 /40 and changed regularly. I was pretty sure that there were no exhaust gaskets when I took the old exhaust off. The new ones I bought (not yamaha genuine) are copper with the asbestos type inner are 4mm thick before compression, I could not get the nuts to start on the thread to do the flange up. Would this cause everything to get a bit hot and cause the clutch problem because the oil is getting too hot?
I have never taken a clutch to bits so am a bit reluctant while the sun is shining! Although I would like to take the casings off to polish them and I don't want to do any damage to the engine. The clutch cable at the lever end was not quite straight.
Thanks again for all the advice Christine
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I could not get the nuts to start on the thread to do the flange up.
Which made me think the gaskets may already be in place.
10W/40 should be fine.
Steve
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I use Halfords 10/40 M/C oil....and filter, and change both regularly......with no problems, for the last 6 years on #1 srx6.
you have deff got the old gasket rings stuck in the head....SteveH is right....they are very well disguised by the muck and coke of ages, and of course difficult to see, but with a lead lamp and a pair of needle nose pliers or scriber you'll find them.....
the r/h engine case is a doddle to remove, just lay out all the allen bolts in the order they came out..... you'll need to remove the de-compressor cable which is easy (but don't change it's adjuster, or you'll have to set it up again) if you are careful you'll save the gasket (as per SteveH's tightwad method) there are lots of things you can check whilst its open as SteveH says....you can even check the oil pump is in good nick (very important, its a pretty poor pump, and can be the cause of major engine failure unless it is in tip top condition)
do you have a workshop manual?
if not i can send you a CD of it, for you to print
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I had a very similar problem recently on the MuZ. turned out to be the gear change lever was a little bit looseon the shaft, letting the change shaft move back and forth. Worth checking, hey?
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Also worth lubricating gearchange lever pivots as these can dry up and partially seize giving your symptoms.
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I will check gear change linkages, a manual would be a big help Steve before I start taking things apart.
Many thanks Christine
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Christine....Email me your contact details >>>> pightlefarm@lineone.net <<<< and I'll send you a CD