FAST IDLE

[Dell Boy]

My Grey Krauser Commander has always run very , 80-82 degrees. This has meant it takes awhile for it to be hot enough to retard the ignition from ticking over at 1,500 revs until at about 88/90 degrees it retards & drops back to a steady 500 revs.Now with cold weather upon us it takes miles to retard & I sit in traffic revving at 1,500.Any solutions out there?Cheers, Derek.

[MrB]

1) Fit a hotter thermostat for winter running2) Fit a manual switch in series (I think, might be parallel depending on how it wired) with the auto switch - if the auto is slow flick the manual switch to achieve the same effect. Switch it back after the engine had go hot enough to change over the auot switch and you are ready for the next trip.Johnny

[graham]

Oh You lucky devil :-) What a wonderful problem to have!With a little searching at Radiospares http://uk.rs-online.com/web/You should find a similar thermal switch that switches 10 degrees or so cooler. (Std is circa 40 degrees C) Only problem might be, if it switches at too low a temperature, it'll stall at the most inconvenient time.Agreed MrB a thermostat opening at a higher temperature is probably the best way, it concentrates the heat right next to the sensor until the thermostat opens.One more thought, try some thermal paste under the thermal switch. ( Ask any 10 year old computer whizzkid for some).I'm genuinely pleased you have the problem, I've spent years trying to make the darned things run enough to survive!Keep clocking up the miles.Graham,Graham.

[Dell Boy]

Thanks for the advice guys.Cheers, Derek.

[Dell Boy]

Oh, by the way, it also changes gear sweetly though not so sweet when revving at 1,500.When I pull my modified clutch lever in & under the handlebar I can feel the clutch diaphragm click as it goes over centre & takes the pressure of the plates.This has proved to me 100% that the problem lies in the inadequate lift with the XJ900 clutch lever & not with the clutch or gearbox. Its only taken 20 years & countless clutch stripping & cleaning sessions to finally get a reasonable gear change.Listen to it, Snick = 1st., Snick, 2nd. Snick, 3rd. Two snicks back & theres NEUTRAL!!! Lovely Jubbly!!!!Cheers, Derek.

[MrB]

Oooo, back on the clutch comments again - can't resist it!!I'll float this idea again as It didn't generate any feedback last time (that I remember). I agree that clutch lift on the manual clutch is the main cause of drag.Clutch lift on the manual clutch is determined by the distance that the balls roll up the ramp of the countersinks in the fixed lift plate. This can be increased by increasing the angle of rotation of the moving plate as Del has achieved.Lift could also be increased by keeping the same angle of rotation but increasing the angle of the countersinks on a thicker fixed plate. It would mean a heavier clutch but this might be a satisfactory trade off for increased lift. Has anyone tried it?Johnny

[commando-rotary]

I have mentioned this before but both my rotaries gear change sweetly and finding nuetral is not a problem my answer to the problem was to (fine) shotblast the bronze plates to deglaze them and eliminate stiction and run the primary drive on 5/30 oil. Any clutch running in oil stiction is often a problem, yes a bit more lift would be nice but it is always a trade of with the weight at the lever. If any gearbox oil should get past the seal behind the clutch, the clutch will never disengage.D G

[Dell Boy]

I didn`t clean the plates or change the oil prior to fitting the Diversion lever.I went straight from a gearchange that wore a hole in the top of my foot & would lock up between 2nd. & 3rd to one that changes as any other bike does. I could only get neutral by turning the engine off when stationary at traffic lights etc. prior to this modification.15 minutes work & the bike is now a pleasure to ride.Now to sort out the running. I will try a hotter thermostat as afirst step.Cheers, Derek.

[Dell Boy]

P.S.I would class the clutch action as being between light & medium.It is not as light as my Dominator or Vincent twin but not as heavy as my Laverda or Commando`s I have owned. I believe the pivot point gives much better leverage with the result that the clutch action is lighter than the original XJ 900 clutch lever.Cheers, Derek.

[Dave]

Regarding the clutch lever, is the standard one off of a xj900,? ? the rotary clutch appears to operate like a trident one, and they have the same problems on some bikes, and different people have tried various ways of getting extra lift, including changing the angle of the operating ramps, on mine i changed the clutch lever and then bent it to give me more lift, it works other than being a long reach to the lever,(and my trident clutch, realy is heavy), i was wondering about trying the same with the rotary clutch lever, hence the question, i would like to buy a spare lever to try on, dave

[Ian]

OK, well rather than spend pages discussing the cause(s) for the clutch stiction, since we have a member of this forum who seems to have found the definitive answer can I ask him for a blow-by-blow account of how he did it?Because then I'll do it too..Ian

[Dell Boy]

Purchase 1996 to 2,000? Diversion lever complete. Remove L/H grip & release switchgear screws.Disconnect clutch cable from clutch blade.Remove complete clutch lever & pivot clamp.Carefully heat Diversion blade & bend it downwards about 10 m.m.You could try it first to see if it will travel under the bar grip without bending. Mine did but it is slightly bent from accident damage.Fit Diversion clutch lever & re-connect cable.Make up a piece of bent flat metal filed into an arrow shape that will enter the restraint hole of the switchgear.Dogleg it up & over the mirror threaded boss with a double bend.Drill a hole in it to line up with the threaded mirror boss & bolt it on to the boss.Smear petrol in rubber grip & push back onto handlebar.That`s it.Derek.

[Ian]

Many thanks indeed.That's it then. I'm going to have a go at this, because if that is indeed all the solution is, well, we should all do it.Thanks again.

[MrB]

I wonder what happened to the proposal of a hydraulic conversion using an expanding bag? Sounded brilliantly simple.

[johnbirchjar]

Hi guys,I seem to remember talking to Del Boy about this clutch drag thing but I think he said that the clutch leavers on Classics and Ip2s were not Yamaha,but would his new system work for air cooled's ?regards J.B.

[Dell Boy]

Hello John, I have a couple of spare Diversion levers. If you want to pop round we could see if they can be fitted to a IP2/Classic. Give me a ring. Cheers, Derek.

[rustynuts]

Whilst on the subject of curing clutch drag, is there any more news on the hydraulic clutch conversion availability? When I spoke to Peter Morris earlier this year he said ANIL may produce another batch of clutch slave cylinders if there is sufficient interest. I think somewhere on this forum Richard said he would ask Peter to produce a batch if there was sufficient interest from club members and that he would do the machining to the primary cases to fit them.

[vontripper]

hi all,re hydraulic clutch, Andover Norton i got this reply from them 4 dyas ago....The hydraulic clutch option will be available towards the end of February.Apologies for the on going delayvon

[vontripper]

hi all,re hydraulic clutch, Andover Norton i got this reply from them 4 dyas ago....The hydraulic clutch option will be available towards the end of February.Apologies for the on going delayvon

[Dell Boy]

I fitted to the Red Commander today a Diversion clutch lever. The clutch on this bike was better than most I have had & a hundred times better than the Grey Commanders clutch.Having fitted the Diversion lever I went out for a ride & the gear change is much improved.I had put my hand up for a hydraulic clutch but will not now be following that route as I am reasonably happy with the gear change now.Derek.

[Dell Boy]

I rode into Central London today on the Red Commander. I did this last week as well.Last week it was prior to fitting the Diversion lever. Gear change was sufferable but I could only get neutral on the roll & with a bit of difficulty.Today gear change was sweet, neutral very easy to find on the roll & I could mostly get it easily at a standstill but occassionally I had to rock back & forward to select neutral.I am going to bend the lever to get that little bit of extra lift that I have on the Grey Commanderto see if that will do the trick.This was a back to back test & showed what a great improvement the Diversion lever gives.Derek.

[bodgerbloke52]

I know I am way late on this thread but I can ad some recent info on clutch drag.My Commander is new over from Holland/UK, came all in bits. Just had first maiden voyage.Clutch drag is a nightmare, spoils a fine ride. It does have the hydraulic operating conversion, all in perfect order, no air in system, properly adjusted, correct rebuilt 5/8 yamaha M/C.About to get in at the clutch to see if I can find summat. Why on earth has it got 18 plates, surely this is the root cause of the consistant reports of clutch drag??????? My other bikes all have clutches that clear at less than full pull in some cases, including two Ariels and a 61 Easy Two that some times I have to release the clutch momentorilly because the gears are head to head.1200 BMW with 110 horses has light action and perfect clutch disengagement. Had a diesel truck once with muti plate clutch, it was a nighmare untill converted to single ceramic plate.Roger in the Pacific NW

[Bob]

This thread seems to be about clutch drag, so this is what my post is about.The clutch drag can be tested without the engine running, put machine on it's centre stand rear wheel off the ground place say a 5 kg weight onto the rear tyre so the wheel tries to reverse, then try to disengage bottom gear, the drag is also a function of the draw angle on first gear, this was changed from 4 deg? To 1.5 deg? (Not F1) to reduce the drag load, when it was reduced the next problem was due to the cam plate chasing past the neutral detent, so it was all a fine balance, Doug Hele came up with a very good solution that involved a peg that moved out of the way only when the lay shaft was spinning, this involved changing the detent profile, the problem being that if you stalled the bike in higher gear you could not get back down to neutral, sort of stalled this development. I just wanted to point out a way of simulating the problem on the workbench to take some of the guesswork or wishful thinking out of the test.On the non outrigger bearing machines, try holding the brake on as above and depressing hard down on the top run of the chain, this causes the sleeve gear to bind on the main shaft and causes drag for the gears to slide in or out of neutral.

[wust588]

Bob, I've often wondered what Doug's modification involved, mainly because it's fitted to my old air-cooled- the "Wust". Remember that?Well, it's still running beautifully with about 110K covered and I still love it to bits.You are dead right of course, the neutral finding is always perfect, but it still occasionally catches me out, if I stop in any highter gear than 1st- I slip the clutch a bit and it soons changes down as normal.I'm on this thread because of my sins- I'm still working on these fine bikes, and have a bad case of clutch drag. Short of setting fire to it, I'm running out of ideas.I'm trying to remember all the things we used to do at the factory to cure this problem.What a great bloke Doug was though. I think he'd be pleased I'm still using the "Wust".John.

[Bob]

Hi John,Do you want me to look in the Wust file as I still have the mileage log book?Bob

[Bob]

John,Clutching at straws.If you are on the centre stand in first at say 1000 rpm, when you clutch in and brake (rear) when you let the brake off does the wheel start to spin up again, most did this to a greater or less degree, if it is really powerfull with clutch lifted fully then I would suspect a couple of things.Clutch drum bearing worn so the thrust is being coverted to torque, any torque is bad for first gear selection.Clutch drum bearing allowing the Drum back face to foul the back of hub.Ist gear drive spline worn allowing the dogs to go out of line, you say that you have had in the past a good neutral finding, what level was this, a Pass, a just pass passed, a just pass, pass, pass, or a fail.It's a bit ironic but slight binding of the 5 th gear or mainshaft can to a point help first gear as it unloads the torque (due to clutch drag) off the 1 st gear drive dog, however even this if extreme can lead to bad neutral finding.Check 1 st gear Layshaft near it's mionor diameter to check if it's worn and trying to ride up the Layshaft major diameter chamfer, some chamfers at or above top limit could allow the gear to self lock on it's shaft and not slide well?This is what I found wrong when I rode RH bike when for 2 meetings ending in 2 nd place at Oultan Park, Barry was getting upset and I was getting the blame for poor gear change and it was being blamed on "Dominator" clutch , Chris Mayhew and myself stripped the bike and we found the problem, you see some of the gears wa designed as bottom fitting and the gear had been made over size on bore, so the gear was self locking on the chamfer.The clutch always get's the blame.Bob

[wust588]

Bob , thanks for the reply.I've cured the bike, the fire brigade has just left.Joking apart, the commander I'm working on was given to me as a "basket case" to assemble into a running bike- as best I can.A lot of the bike has been damaged at some stage, and it looks like several experts have had a go at it over the years. Then it was left to rot 15 years ago. You get the picture.I think I've got to the bottom of the clutch drag after stripping and building a few times. After binning a couple of bent plates, a slightly warped pressure plate and scrubbing the bronze plates, it's now stopped dragging.The clutch action is like the usual on-off switch, so when the owner collects the bike, I'll give him a set of the early unhardened clutch lift plates and 10mm balls to try. I have these on the Wust and they have always worked beautifully.Regards,John.

[Bob]

John,Good news,If you ever need to read the Wust log book file let me know.Bob

[wust588]

Bob,Thanks for that.I do have the original Wust development hardbacked build/parts change/mileage record and rider's notes logbook.I treasure it as you can imagine.John.

[Bob]

Sorry John,Shucks and I thought that I had all the log books? I have not read them for years, the saying goes "it's all in the book".Bob