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M159 Fork Oil Bolt And Clutch

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I wanted to replace the fork oil but the allen bolt that drains the oil out on both forks just spins can not loosen or tighten, I did go ahead and add some fork oil because it appeared empty and it almost immediately started to drip from the bolt. Why? and How? do I fix. I am also having a difficult time setting up the clutch pressure point using the adjustment screw and jam nut. Any tips beyond the manuals. It works but just barely difficult to engage and grabs quickly. I did have it set up so I could use the clutch lever to disengage the gear box but it then would not kick over ( did not catch)

Sunny

Hi Sunny

On the forks .. if you are talking about the allen head screw on the very bottom of the forks , that is the screw that holds the damper rod in place and the forks together basically. What you need to do to tighten it or loosen it for that matter, is if you look down the fork tube from the top of the fork leg (fork cap and spring removed) you will see the top of the damper rod. It has a slot machined at the top of the damper rod and you will need a very long flat blade screw driver to hold the damper rod while you turn the allen head screw in or out at the bottom of the fork leg. That is probably where your oil is leaking from so you may have to remove the screw and reseal or regasket it. There may be a small sheet metal oil deflector that the fork spring sits on so that will have to be removed also before you can see the damper rod. I had to grind the handle down on an old screw driver to modify it enough to fit all the way down in the fork tube far enough to engage the damper rod. I have also heard that you can put a longer bolt thru the drain hole port to jam the damper rod but that didn't work for me on assembly because it pushed the damper rod out of alignment and I couldn't get it tight enough without fear of damaging something.

I am not sure what to say on the clutch issue as I have not gotten into mine yet.

I hope this helps.

Sam

Hi Sunny

There have been some very good step by step posts on this forum about how to set up a Bultaco clutch. Click on search, choose the Bultaco heading and enter Bultaco Clutch then perform the search. Lots of threads will come up but one about trying to get one finger clutch operation on an M199 was very useful I remember and another by John Collins was also very helpful.

Getting an old Sherpa clutch to be smooth starts with a strip and making sure all the components are correct and servicable then following the setups mentioned above. Just changing the plates is not the answer. If, however, you do change the plates as part of the rebuild I have 'Barnett' plates in my Alpina and Bultaco Frontera plates in my Sherpa. Both give a better clutch feel than the original I would argue. Always use a lined clutch cable (such as the Venhill cable).

Tim

Hi, the easiest way to tighten or loosen the bolt at the bottom of the fork leg is quite simple, put your bike on your trailer and using tie downs, compress the forks as much as you can, this will apply enough internal pressure to the dampner rod via the fork spring to stop it spinning, you will now be able to either undo or tighten the allen bolt. This method has never failed me, so fingers crossed it should work for you as well, Cheers Greg

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