is 7/16 of spline enough to hold the front pulley on?

[Moespeeds]

Hey guys, after installing my new belt drive I'm having an issue getting my front pulley tight enough. I munched two charging rotors this week, and the nut backed off last weekend, seizing my belt drive. On the advice of a mechanic friend, I'm mounting a heavy duty rotor, it has double the spline depth of stock so I wanted to mount it with no washers. I still can't seem to get that sucker tight enough, so I've also added a small washer, about the depth of a penny. Even without the washer I'm barely pushing 1/2" of spline sticking out for the pulley to grab. With the washer I'm about 7/16". Is this enough spline area for the pulley to hold onto? I'm running an S&S 117, with a 3/38" Ultima belt drive. In the pics below I've already torqued the nut on, then took it off for the photo, so the crank and flywheel should be pulled into position.

 

[Gas Man]

I had about the same amount spline on my install but maybe more

But make sure your pulleys are flush on the face. Otherwise the belt won't track correctly.

but you should invest in a kirk's custom's front pulley locking plate! Tell him Chris (RMD customer) & Al from Michigan sent you.
http://www.kirkscustoms.com/

 

[Moespeeds]

Actually Gas I was planning on safety wiring all that. I emailed Kirks but I want this thing on the road, I'm too impatient to wait. My new nut is open on the top so it would be pretty easy. Why does your shit look so much cleaner than mine!

 

[bdmridgeback]

Because Gas' bike was "Brand new" and never riden in those pics!!

 

[CCRainman]

Moe, I don't think it'll hold. The spline seems a little short with not enough area to grab. Mine was a lot more then that like Gas said. I don't use the locking plate and mine has been fine. I rather be safe then sorry.

 

[alhall88]

Can't remember but I know I had more surface than that. The recessed pulley went inside the motor plate and I have never had any issues but I still run a lockplate as well. The thing is here that the S&S cranks are known for some runout so this would only magnify this condition if it exists with your crank.

 

[CCRainman]

Now that you guys are on the subject, since Al and Gas are both running lockplate. Maybe I should go get myself one of those for security.

 

[Gas Man]

Now that you guys are on the subject, since Al and Gas are both running lockplate. Maybe I should go get myself one of those for security.

That's it Rain... and its not expensive. The RMD's use the same as the Primo but due to me Kirk already knows that.

Jake is right but also mine is chrome not polished.

 

[CCRainman]

I just ordered one today from Kirk.

 

[alhall88]

Now that you guys are on the subject, since Al and Gas are both running lockplate. Maybe I should go get myself one of those for security.

Good call, although the whole time I've had my belt drive I have never had that nut back off ,the 2 stators that I had to replace with the old setup is still pretty fresh in my memory.

 

[T Mack]

Dumb Question??

Just curious of how much you guys had into converting to belt drive?
One thing that i have always wanted to have....

 

[Moespeeds]

Belt Drive plus machining to make it fit my 1-7/16 offset- $1500

And the following due to my mistakes installing it:
First charging system/voltage regulator - $225
Second charging rotor - $60
Third charging rotor - $150

I'm installing the 3rd rotor this afternoon, hopefully this will be the end of my torment with this thing!

 

[T Mack]

Belt Drive plus machining to make it fit my 1-7/16 offset- $1500

And the following due to my mistakes installing it:
First charging system/voltage regulator - $225
Second charging rotor - $60
Third charging rotor - $150

I'm installing the 3rd rotor this afternoon, hopefully this will be the end of my torment with this thing!

Hope it goes smoothly

 

[TCALZ06]

Belt Drive plus machining to make it fit my 1-7/16 offset- $1500

And the following due to my mistakes installing it:
First charging system/voltage regulator - $225
Second charging rotor - $60
Third charging rotor - $150

I'm installing the 3rd rotor this afternoon, hopefully this will be the end of my torment with this thing!

$1500 is cheap. I thought these were about 3k+ it looks good

 

[Moespeeds]

Yeah the only issue I had was with the 1-7/16 offset for the Daytec 250, but it was only about $75 to machine the motorplate and pulley. I solved my problem this afternoon, it looks like what happed was when the pulley came loose originally, the flywheel and crank moved all the way to the right side of the bike. Today I cleaned out the front pulley nut really good, then spun it all the way on without the pulley on to clean the threads. Apparently there was a nice glob of red locktite in there that was causing me to reach the max torque on the gun before the nut was fully tight. This made everything feel tight, but when I grabbed the pulley there was about 1/8" of lateral play there. A buddy spotted the problem, and we got it sorted out. I put everything back together, and safety wired it all just for Gas.

 

[Raywood]

Yeah the only issue I had was with the 1-7/16 offset for the Daytec 250, but it was only about $75 to machine the motorplate and pulley. I solved my problem this afternoon, it looks like what happed was when the pulley came loose originally, the flywheel and crank moved all the way to the right side of the bike. Today I cleaned out the front pulley nut really good, then spun it all the way on without the pulley on to clean the threads. Apparently there was a nice glob of red locktite in there that was causing me to reach the max torque on the gun before the nut was fully tight. This made everything feel tight, but when I grabbed the pulley there was about 1/8" of lateral play there. A buddy spotted the problem, and we got it sorted out. I put everything back together, and safety wired it all just for Gas.

Moe, may just be the angle or something but that sproket doesn't look centered on the shaft! Looks like it would wobble and cause lots of vibration.

Is it just the angle? Nice wiring job also.

:flag:

 

[Gas Man]

Mo...got a better pic of the wiring? Did you drill the crank shaft?

 

[Moespeeds]

That's the angle Ray, the nut sits about 1/8" proud of the "floor" of the pulley, and I'm taking the shot from a downward angle. It all runs true, I took it out for a ride today. You can see the crank down inside the nut, with just about 1 thread left on the nut itself. Before I got it really tight, I had better then 1/4" of thread unused on the nut, that's how loose I had it! The orange in there is nail polish I originally used to see if the nut was moving. Didn't drill the crank Gas. My nut is open at the top, so I drilled all the pulley bolts, and 2 holes in the nut near the top. Sorry, just had my cell handy for the pic. The piece of wire you see on the lower edge that looks like it's running down in the crank is actually just the pigtail, I pushed it down in there.

 

[Gas Man]

So you drilled the nut that isn't completely engaged on the crank... right?

 

[Moespeeds]

Yes, but you'd have to see the nut, it's hard to tell from the picture. The nut has two parts, the threaded portion fits down in the pulley neck, and the driving portion. Right now if you look closely, the threads are fully engaged, and about 1/4" of the driving portion is sticking up out of the neck. I drilled the holes there, basically I got lucky and they landed right where I needed them. Then I drilled the heads on all the cap head pulley bolts so I could wire it wherever I needed it. I was planning on drilling all six sides of the nut and going apeshit with the wire, but my buddy is really old school and he was sitting there busting my balls that I should just drive it home and stop worrying.