kickstart pinch bolt question.

I bought a salvaged bannana shaped kickstart lever off.... yeah ebay... so I could get clearance for my rear sets. Pictures on ebay showed the splines were in good shape and they certainly are. I think the reason they are in good shape is because someone stripped the pinch bolt threads early in it's life so this lever sat in someone's parts bin until they decided to tap it to a larger coarse thread and sell it on ebay to some dumbass (me)

My question is,...was the pinchbolt threads on a kickstart ever made in a coarse thread? and if I take a chance and use it as is, instead of returning it, do you think it will hold up with this coarse thread bolt?

Thanks for opinions...

o0norton0o said:

My question is,...was the pinchbolt threads on a kickstart ever made in a coarse thread?

Click to expand...

As far as I am aware, the standard kickstart pinch bolt thread for all Commandos was 3/8 - 24 UNF.

https://www.oldbritts.com/12_061464.html

06-0599 Kickstart Bolt, 3/8 UNF

Click to expand...

I have re-threaded a couple of them. The one I have now is a coarse thread. Make sure you use a grade 8 bolt or better. Socket head of course. You might be able to heli-coil it back to the standard thread but it sounds like it is already too big for that.

I have also been known to build a custom insert to get a thread back to the stock size. That you would have to lock-tite in place making sure to "load" the thread toward the tension side as the lock-tite sets up.

hopefully you got a good price because of the problem and once solved you will be set.
Dan.

Yes, at least grade 8 bolt. Use a flat washer under the bolt head and a long bar to tighten it, once you've figured out the correct thread. Mine used to get loose all the time, the previous took care of it.

When tighten my kickstart pinch bolt, I tighten to the point where there is a definite stop. This feel is somewhat obvious and that is where I stop. Always seems to hold.

pete.v said:

When tighten my kickstart pinch bolt, I tighten to the point where there is a definite stop. This feel is somewhat obvious and that is where I stop. Always seems to hold.

Click to expand...

I check mine most everytime before I ride. Its usually tight.

I bought it off ebay for about $80. It's tapped out to a 3/8ths coarse thread. I sent a message to the seller about it. I'm willing to take a chance with it if he refunds me $40. Then, I'll do whatever I need to do to make it work, or accept it's failure and find another one if it comes to that. I wonder if a helicoil would stand up to the forces a kickstart lever is subject to... and If I could helicoil it back to 3/8ths -24 in it's current condition.

o0norton0o said:

do you think it will hold up with this coarse thread bolt?

.

Click to expand...

The general rule is - coarse threads for strength, fine threads for resistance to loosening.
However it seems that someone has tapped this piece from 3/8" UNF to 3/8" UNC, so the threads will be incomplete.
If you try tightening it, it may strip out, in which case you will have to apply one of the repair methods suggested. And/ or talk to the seller.
If you can achieve a good tight clamp on the shaft as it is, all may be good.

Heli coil repairs art typically stronger than the original thread. A completely stripped 3/8 thread should take a 3/8 heli coil. Usually a 3/8 stripped thread is just a 3/8 straight hole. The trick to successful heli coil use is to "load" the coil toward the tension side as the lock-tite sets up. A lot of people just put them in with lock-tite and let it sit but you have to put a bolt in and pull it in the direction that it will be pulled later so that on the tension side of the insert it is metal to metal and all the lock-tite compound is around on the other side of the insert threads. It is a small trick to pull off since the lock-tite will try to lock the bolt in as well. Just put a small amount of anti seize on the bolt, covering it completely with a thin coat and screw it in. Apply light torque and wait over night. Next day when you take the bolt out it should come out without the heli coil. All of this needs to be done on absolutely clean metal so use brake clean after you use the heli coil tap. Clean the heli coil itself too since it could have oil on it from the package. Also, don't skimp on the heli coil length. If there is room for 3/4 of an inch of threads then use a long heli coil to take up the whole length. You'll need a corresponding length grade 8 bolt. I also recommend using fine thread on steel since it is a bit stronger than coarse in steel. Don't skimp on the lock-tite either, cover the whole insert and put some down in the newly threaded hole. (Red, High Strength)

And, the heli coil should not protrude out either end. From the start side it should be at least a quarter turn in from flush. On the back side it can be ground down flush or maybe it will be just shy of sticking out any way. Should hold better than a new one.

Thank you all for your opinions and helpful suggestions. The guy from ebay got back to me and said he didn't realize that the bolt hole wasn't original threads and was rethreaded to a 3/8th coarse thread. He refunded me half of what I paid for it, so I am out $40. for the kickstart, but it's my problem to make it work now.... I put the new kickstart lever on and carefully torqued it down as much as I dared with Red locktite 275. We'll see if the coarse threads hold up for a while, before I am forced to helicoil it back to 3/8ths- 24.

Again, thank you all for your collective wisdom...

What I did to my one of my kick start lever was to get a longer bolt with the same thread so the bolt could be scewed up thigh with enough thread out at the end so I could also put a nut on you might have to grind a bit at the end of the kicker so a nut can sit proper, once I did this to my kicker it never came loose again in the 30 years of running it, but now I am running a T160 folding kicker (from RGM) and have so for over 7 years now without any problems with it coming loose and the best thing with this kicker it's longer and swing right away.

Ashley