Starter Ring Gear Hitting Motor Plate On BDL 3" Belt Drive

[NevadaSmith]

I have a BDL EVO-9S 3" Open Belt Drive on a S&S 96" Evo & a Jims 5-Speed Transmission in a kraft tech softail chain drive 180/200 frame, Electric Start.

This is one of those projects that's been stopped & started on & off again over a period of years... "Ran When Parked" 🤣

So the current issue is I noticed the starter ring gear is hitting the inside of the BDL Motorplate, but very little; like it needs to be shimmed out a little bit from the motor plate. I tore everything apart for inspection, paint, polish years ago so I could have lost a shim and I have not started it since i put it back together because I'm changing up the controls and some other things unrelated to this issue.

But in looking at the BDL Instructions, diagrams and parts they itemize I don't see anything missing or any shims listed that would move that starter ring gear out from the motorplate/belt drive inner primary.
There's just the rear basket, with the starter ring gear, the bearing and snap ring.

http://beltdrives.com/open-drives-2/belt-drive-kits-for-softail-and-dyna-models/evo-9s

http://beltdrives.com/wp-content/uploads/2021/10/83inesd-86up-softfxr.pdf

This starter ring gear being to close to motor plate on a 3" BDL Open Belt Drive sound familiar to anyone?

thanks in advance.

[JBinNC]

If the transmission has a splined mainshaft, check that the clutch hub will rock on the splines. If so, the clutch assembly may rock enough for the ring gear to hit the plate. We are dealing with this now, clutch assembly is moving enough to make the belt track off the clutch shell.
Solution is a new clutch hub.

Jim

[NevadaSmith]

If the transmission has a splined mainshaft, check that the clutch hub will rock on the splines. If so, the clutch assembly may rock enough for the ring gear to hit the plate. We are dealing with this now, clutch assembly is moving enough to make the belt track off the clutch shell.
Solution is a new clutch hub.

Jim

the tranny mainshaft and hub are brand new, i had to replace them as part of this project. I have not started the bike since i replaced them only turned the engine over by a socket and rachet to check belt alignment and final drive chain alignment which looks good.

it does look like the starter ring gear is hitting motor plate slightly on one side, but not all the way around, so maybe it's the key or something.

[Revelator]

If you have the old clutch hub, compare it with the new clutch hub, using a depth micrometer.
I'll bet the distance from ring gear mounting face to back side of hub is Different.

IMPORTANT:
A Shim cannot go up against the bearing on the motor pulley, If It did, It can severely
damage the transmission because the trans shaft would be forced outward (or Pulled outward)
When the clutch hub nut is tightened down. (Similar to when a bearing is pulled off of a shaft when
using a typical bearing puller). This because the shim would be moving the clutch hub away from the
end, or edge of the spline, creating a gap, rather than butting up against the edge, So when the clutch
hub nut is tightened, The force would "Pull" the trans shaft outward until that gap (created by the shim)
is reduced.

The ring gear could be thinned down (on the side that rests on the clutch hub)
using a surface grinder (precision ground). But only by a small amount, like maybe .020
(enough to stop the rubbing). This should not affect the engagement of the jackshaft gear in
relation to the ring gear.

Make sure you lock tight those screws that bolt the ring gear to the hub.

[JBinNC]

If it is a splined mainshaft, you can put a shim against the splines, because the captured washer in the clutch hub is what sets the installed position.

But I think the OP said his clutch hub was keyed, so no shimming is possible.

Jim

[Tattooo]

Pics would be very helpful...............

[NevadaSmith]

If it is a splined mainshaft, you can put a shim against the splines, because the captured washer in the clutch hub is what sets the installed position.

But I think the OP said his clutch hub was keyed, so no shimming is possible.

Jim

I mispoke, mine is the splined inner clutch hub, not the keyed one.



It does seem like maybe it's cocked a little like you found with yours, but my belt seems to track straight...
there's not a good way to take pictures of the ring gear hitting the motor plate with the drive & clutch assembled, i still have the old hub i replaced, they're both the same BDL part. I guess I'll pull it all apart and start measuring shit, and see if I can find out what's different from when it was torn down. I thought maybe I lost a shim or something but it don't look like they're designed to have any.

[NevadaSmith]

So my alignment issue was a little bit more involved than I expected. After finding no difference between old & new BDL parts...
I started with some precision shims from McMaster-Carr that would clear the transmission main shaft and ride on the motor plate bearing inner race and the clutch hub which seemed the logical place to start. Could not find any scenairo where BDL or H-D ever put any shims there, but everything seemed to indicate that's what it needed.
a .030" Precision Shim at first glance seemed to do the trick. But after watching some youtube videos from BDL and others on their 3" belt drive install and downloading instructions from BDL's site I discovered my belt drive was never setup right by whomever installed the belt drive before I bought the bike. I found the motor plate bearing was blown when I got the bike, and it looked like I just needed to replace the bearing... but going down this alignment rabbit hole I found a bunch of miss-matched parts were the untimate problem and the likely cause of the bearing failure to begin with.
I ended up needing a PS-250 1/4" Motor Plate Spacer from BDL, to compensate for offset built into my particular Kraft Tech softail frame.
I also needed the SK-2 front pulley shim kit from BDL. I used the .100" shim to get the special stepped BDL front pulley nut to tighten up against the sleeve like their video emphasizes.

BDL Open Belt Drive Install:

https://youtu.be/2qfKMSSt_vg

BDL Tips & FAQ's:

http://beltdrives.com/tech-tips-and-faqs

BDL Install Guides:

http://beltdrives.com/install-guides-and-warranties-page

BDL Front Pulley Special Insert:

http://www.bdl-sales.com/IN-250-14-SPECIAL-INSERT-SPECIAL-NUT_p_466.html

BDL Belt Drive Install with good tips & tricks:

https://www.bikernet.com/pages/Sturgis_Shovel_13_Final_Assembly.aspx

BDL Belt Alignment Troubleshooting:

http://www.clubchopper.com/forums/shop-talk/30065-bdl-belt-drive-stock-spacer-behind-front-pulley.html

Another BDL Belt Drive Install with good tips & tricks:

https://www.bikernet.com/pages/story_detail.aspx?id=1973&id=1973&id=1973&id=1973

BDL Belt Drive Clutch Hub Install Troubleshooting Tips & Tricks:

https://www.jockeyjournal.com/threads/bdl-competitor-clutch-hub-wobble.98822/