I just bought a BDL enclosed primary belt drive for my '82 FLT tourglide....yep, the oddball years with the 5 spd tranny! The kit is made for that model, but the belt is WAY too tight. I can't run it like that. I've been in contact with BDL, and they seem to think the problem is with the inner primary housing. The distance between the crank and tranny shaft is determined by that housing, and it seems to be too wide. I'm a machinist, so I can weld / remachine the bearing bore, no problem...thing is, I'd like to know what the distance should be, to see if it's really off or not before reworking it. Any ideas? (I would think BDL would know since they have to make the kit based on SOMETHING, but I haven't heard back from them.) Any other suggestions on getting this belt tension right? Anyone else been there, done that?

Thanks!

 

that's weird... I am pretty sure the distance is the same also for later years... since gettin a later primary housing and/or transmission (spline shaft) should bolt on

 

To answer my own question: BDL gave me a dimension of 11.327". I guess the 4 spd shovels are 12.900". I measured it at work on a CMM and got 11.324. Still doesn't explain why the belt was so tight. The transmission bearing bore was pretty loose, so I welded it and rebored it on size - AND shifted it 0.020" towards the engine bore. It looks good so far, still need to tighten everything up and see if it's tracking good.

 

i know this is a slightly old thread(few month)

but im running into the same issue on my 80. the belt seems too tight. it has a 48t front(engine) 68t rear(trans) with a 130t belt. i'm thinking of just getting a 132t belt and running a tensioner. or going with a 47t front pulley to gain alittle bit more for the 130t belt.

how did you solve your issue.

 

@cobra99,

Your setup sounds like the same as mine. I took my inner primary cover in to work, and welded the bearing bore on the far side, and remachined it 0.020" closer to the crankshaft. Belt tension is just right now. BDL did mention that some of the inner primarys around that era varied on the 11.327" dimension by 0.030"....sounds like both of us have that longer spacing. That would put the dimension at 11.307" which is about what I machined mine to. Maybe you could do the same, or find a different inner primary with the shorter spacing - of course you'd have to measure it accurately, or figure out all the part numbers involved in those changes, to make sure you get the right one. I'm not sure I'd do it again, after all this trouble...and I expected it to run smoother, it actually vibrates more. It seems they should have a rubber compensator for the front pulley, but maybe it couldn't handle the torque. I asked BDL about using a tensioner, and they didn't like the idea, but that may be a better solution. I might look into it myself, since many of their setups use a tensioner. Hope that helps!

 

back a few years - they sold a belt called the bullseye belt as it was just a bit longer than the stock one they send - i do not know if its still available

 

This one?

http://www.ebay.com/itm/Belt-Drives-...item2a4f517fa4

 

I'm sure adding two teeth would require a tensioner. Let me know if you come up with a tensioner setup that works, I'd be interested to try it!

 

I made mine years aho using skateboard wheel bearings, a plate and a bolt

 

Belt's too tight because BDL changed belt suppliers, I've run into that issue with them several times the last few years and they will try to push it off on you the owner to " correct " things by slotting the primary and bumping it forward a hair.