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1986 Formula MX Attempting to add Electric Start

550 Views 17 Replies 6 Participants Last post by  chriswy27
I'm attempting to perform an electric start retrofit on my '86 PRS sled. The parts seem very hard to come by but at this point I think I've collected most of them. Mostly want to ask, is there anything I am completely overlooking? Below is the parts I've acquired. I think I have pretty much everything minus the battery. My only question is which ring gear to use.

From a couple different '91 PRS Sleds:

* Clutch Part# 417202100 : My '87 clutch didn't have the posts to mount a ring gear. Looks like despite having the posts that this one never had a ring gear installed either as the holes are not tapped. I was worried at first but then read the screws are self tapping.​
* Ring Gears Part #414807500 & Other Part# 414604300 (maybe)?: Below are two different styles and I'm not sure which one I should use. The right one looks like images I've seen online and comes with the Phillips head self-tapping screws which I believe are part# 309903100. The left one I think was the newer replacement once the right was marked NLA by skidoo and looks to use hex head screws part# 732601120. Any idea which gear I should go with?​
* Startor & Engine mounting bracket:
* Wire Harness from a 91 sled with E-start: I believe the missing "pins" marked 1, 3, etc. from the large 8-pin connector are the ones coming from my stator but I'll have to compare my'87 harness there.​
* Ignition w/ E-Start
* Voltage Rectifier
Just want to say that I wouldn't have been able to get this far without Hudson's Sled Salvage awesome parts diagrams w/ oem numbers. Anyhow, am I nuts to attempt this? Will something I've purchased not work the way I think it will? Thanks!​
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Once you put the ring gear on, you should check the balance. Any local machine shop should be able to do it.
Agreed it would be ideal, but did anyone actually rebalance after installing an e-start kit or was it recommended by BRP? Are the gears not made to a certain spec. that it wouldn’t be necessary?
They balance them at the factory. I've only done two and both times had a shop spin them up and test for balance. Doesn't have to be perfect, but the better it is, the less wear and tear on the crank bearings and seals.
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