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78 213 Alpina


jap350
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Yes graham I think you could be right,it has the nuts on the springs on the clutch could be either ,but if only I knew before,I've machined a washer,new drilled nut to lockwire which was missing,all nice and tight now,assembled the clutch ,alignment good,the tensioner doesn't run true so I took it off,and with the mikuni fitted started her up and hallelujah it bloody runs !! Revs and ticks over a treat,I nearly wet my pants cheers for the help, wouldn't have got there without you all,not sure if it was either the carb or missing washer but they've both sorted it,tomorrow I'll take it for a spin before I long wire it up and put the cover on.

I'll let you know how it goes cheers again andy

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Hi Andy. I`m not sure on the clutch with only three springs. Maybe try having all the new springs but back them off five turns instead of four. I put a new clutch kit in mine and I ended up using the old springs as it was very stiff. You could also try a mix of old springs and new ones. I am sure I have read on here of someone using four springs with Barnett plates instead of six. Experiment and find out. Graham.

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Andy, I build and use myself, 4 original springs, nuts backed off 3 1/2, 300cc ATF (dexron).

In my experience 1st plate in must be earless, you may experience clutch slippage if

you don't kick smartly, none when underway, well lubed cable important.

Graham thanks for helping,hope this is what you referred to.

Larry

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Cheers Larry I thought three because it would be even,I use a three spring clutch on my grasstrack bikes which run dry clutches ,

I've run an extra wire from the handlebar switch to the rectifier to try and stop the smaller festoon bulb from blowing,see how it goes,I'm going to leave the mikuni on as it's running good cheers again all andy

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  • 2 weeks later...

Well I've tried different setups with these Barnett plates and I'm back to the six heavy duty springs and all fine until all assembled with oil and it slips still,I've turned them in , and backed them off 31/2 turns then trued the clutch up,I can't have it slipping I can't even start it now,every other kick is spongy,next I'll try pulling the lever in and tighten the springs up tight,what do you think ? Can't see how you run it with 4 springs, Cheers Andy

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heavy duty springs, being stiffer than normal springs, have a higher rate. This means that if you set the spring tension by a certain "number of turns out", you will probably be backing off the pressure plate load more than with normal springs. A better way to approach setting the clutch spring preload is to adjust them until you have just enough load on the pressure plate to prevent slipping when you kick it over cold. You don't need the clutch cover in place for all this, just make sure the plates have oil on them as you assemble the clutch and you can leave the cover off until you get the spring tension right.

Something else to check is that there is no load on the clutch pushrod while you are doing all of this

Edited by feetupfun
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With Barnett plates, I've found that you can only use 4, as mentioned previously, but to keep the correct thickness of the pack I use one steel plate on the outside, so 4 Barnett and 1 steel friction plates and 5 drive plates. As also mentioned previously, drive plate goes into the basket first.

I run all six springs on my Sherpas but with the nuts backed off to get a light pull on the lever. You can't back the nuts off very much as they will foul the inside of the case, so I machine the nuts to half of their thickness. This means they can no longer be lock wired, unless you drill new holes, but I've never had any come undone. I screw then in until the thread of the studs is just showing and then start fine tuning from there.

First thing to do is disconnect the cable and back off the centre adjustment screw in the basket. There should now be a lot of free play on the clutch arm. Rotate the clutch arm as far as it will go clockwise and then screw in the adjuster screw until you see the arm move. Back of the adjuster until you have a little free play in the clutch arm. Now position the clutch arm on the spline so that it is roughly 90 degrees to the cable run, so that the cable is pulling the arm straight towards it rather than having to rotate it around the spline which will increase its resistance. If the arm is as straight as you can get it, it will offer the least resistance when the cable pulls it. Reconnect the cable, adjust up slack, and you should now be able to pull the lever and operate the clutch. If you can't you will have to repeat the above until you can - if the clutch arm or splined shaft is not positioned correctly you can end up with the 'cam' of the operating arm fully rotated against the pushrod before you even pull the lever, so it can't move any further and will feel solid. So if all has gone to plan you should by this stage have a little play in the clutch arm to pushrod and a little play in the cable on the clutch lever.

Once you have the clutch plates moving you need to ensure that the pressure plate is lifting evenly by adjusting tension of individual springs. I've found that on all clutches there can be as much of a difference of one or even one and a half turns in (or out depending on how you're measuring) between springs to achieve this, they're never all at the same tension. Also ensure that the faces of the slots in the basket in which the friction plate tabs run are perfectly smooth and free of ridges.

Once you have the pressure plate lifting evenly, check the pull on the lever, you should be able to operate it with just one finger. If it feels heavy, back off each spring half a turn and experiment like this until you get the pull you want. With the greater friction of the Barnett plates it seems less tension can be used on the springs which helps. Now put the bike on a stand, stand on it and kick start it. If the kickstart is slipping, put a quarter of a turn on each spring and try again until it starts. A bit of slippage on the kickstart isn't unusual but obviously you don't want too much, and bear in mind it may increase when the oil gets warm under normal use. Best way to start the Bulto is clutch in, rotate the kickstart to about 3 o'clock, let out clutch, let kickstart up slightly and feel for TDC by pushing gently. When there, lift kickstart on ratchet until it's in a comfortable position for you and push hard, rather than kicking or thrashing at it. It's less likely to slip that way. If you kick and thrash at it, they can slip on the clutch.

Now ride it to see how it feels and adjust accordingly. Only when that is all finished, put the case back on and fill with oil.

Also, it's worth checking the alignment of the pins that hold the springs and buckets as they are quite weak and can be moved off centre in relation to the holes in the pressure plate. Before fitting the springs and buckets I check their alignment and centre them - easily done by just bending them with a screwdriver through the pressure plate hole. I figure it's best to have them centralised so that there is no binding on the springs / buckets.

It's a bit fiddly but this is how I set up the clutches on my Sherpas and I can operate them with one finger. It's just takes a while to get the right leverage with no or just acceptable slip on the kickstart.

Edit: - Forgot to mention that for a clutch arm, I use the Sherpa front brake arm as it is longer so requires less leverage, as the standard clutch arm is quite short. If you're using the standard clutch arm, you probably won't get as light a pull on the lever.

Edited by woody
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Hullo all,I have been following this all along,loads of good advice given.I think most riders will get a difficult clutch at sometime.Yes,I had one recently that refused to behave.Here are 2 additional things I do. I put the centre hub in the smaller of my lathes( an Emco) then turn by hand slowly with a cutting tool put in backwards-- so as not to cut-- just touching the 6 mm studs.It is then an easy job to gently bend each stud with a short piece of tube to get each one exactly in line.It is amazing just how far out some of them can be! My second bit of " fine tuning" is to check the half round guides,( for need of a better word) the inner drive plates bear against. If grooved or indented at all I carefully dress with a diamond file. The end result is a nice smooth non grabby clutch. Hope this helps,John, Island of Jersey.

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Just wanted to thank Woody for the detailed clutch set up instructions.There is a lot in there that I haven,t been doing and probably explains why I wasn,t able to get the clutch working properly on my sherpa t.I can,t wait to get out and work on it.

Thanks again! :thumbup:

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Scott, you never asked that I remember, but THANKS WOODY !

Great help for all.

As we know Andy has a bit of an odd setup (duplex chain) the pressure plate cannot bottom out on the hub,

and will only line up one way on hub & studs, the number of plates should stack up the same as the steel,

(if it worked before)?

Larry

Edited by lbhbul
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