Originally Posted by KCvale
Hi, welcome and good luck with your first build!
Unless your seat tube is too fat for a good fit, don't put anything there other than maybe a little locktight.
And pinning it won't counter the twist, that is what your front mount is for.
If it all possible use the dual stud mount so you have a stud on the right side of the front tube, that will counter the twist the best and it is a much longer lever than a pin at the pivot point.
As you read through the myriad of tensioner ideas here you will find one common mantra of mine, if it is at all possible DON'T USE ONE ON THE DRIVE SIDE!
If chains won't match make the pedal side long and put it there.
You won't need to worry about rubber or pins or anything, the pedal side is human power and seldom used.
You don't need to use the big ugly hunk of metal tensioner for the pedal side either, a nice little one like this works just dandy.
All my pedal side needed after getting the motor side right was a single 1/2 link.
I hope that helps ;-}
Thanks for the encouragement and especially the tips. This first build has been over a year in the works mostly because of work/family obligations.
Anyways, I know you mentioned that the front mount helps with the twist of the engine but I like the thought of a properly triangulated mount setup. That would obviously work the best. Two mounting points can work very well if you weld in solid mounting brackets onto the frame. With the stock straps i would think there's always a fair potential for twist unless you do the nuts up really, really tight in which case you run the risk of pulling the studs out of the case. I love your idea of the tensioner on the pedal chain though since unless all the planets are in perfect alignment and you luck out you're bound to end up with one of the chains either too loose or too tight especially if not running a derailleur to take up the slack on the bicycle chain.