RGM belt drive issues

I purchased a "belt" drive kit a while back and have installed it with some issues.

1. The engine sprocket never gets “set” on the crank. Gets pretty close to the cases but works ok.

2. The button headed bolts on the back of the clutch basket needed to be ground down as to not rub on the inner of the inner primary. Works OK now.

3. One inch up and down play needs to be obtained to compensate for the swelling of the Anodized Aluminum clutch basket. This is “almost achievable but the gearbox is at the limit of adjustment in the cradle. Stock belt with kit too short?

4. Due to the extreme amount of swelling of the clutch basket when hot, I lose clutch function. The adjustment at the lever disappears and I have to screw out the handlebar adjuster on the fly to actuate clutch.

5. Also I believe the clutch basket swells to such an extent that it is possibly binding the drivers causing the clutch to drag at stop lights and make it impossible to find neutral and causes hard shifting. Once cooled down, all returns to smooth operation.

My primary is opened up quite a bit for air flow.

I am not sure what size a stock belt would be, but this one appears to be too short.

Any suggestions that would help with these problems would be truly appreciated.

Thank you,
Peter

One inch total up and down cold movement is not enough.

You should be able to twist the upper belt when cold almost 90 degrees.

Seems like they maybe shipped you a too short belt in that your gearbox is full forward and still too tight.

Have you call RGM and requested they send you a bit longer belt?

Possible your belt was stamped incorrectly, correct numbering size but out of a shorter batch maybe?

I would not ride your bike until you get the proper sized belt.

My belt primary is a Norvil, now ten years old, still set in the middle of the gearbox range.

highdesert said:

Have you call RGM and requested they send you a bit longer belt?

Click to expand...

Yah, I sent a duplicate of this posting to RGM hoping for some resolution.

1 .Common problem, sometimes I have needed to remove a bit of material from the backside of the engine sprocket center to keep it from touching the cases. Beyond that I have not seen failures there.
2. Sounds like maybe the clutch locating snapring is not holding or you need to add washers to move the clutch hub away from the inner or move the inner back if the stud in the center of the rear cover is holding it out too far.
3. If you have 3/4 inch with your foot on the rear drive chain you have enough play. Otherwise you may have to file the slot so the trans can move forward a little farther. The next size larger belt is a lot larger and will not work.
4. Swelling of the clutch drum can not be enough to affect the clutch dissengagement. Something else must be happening. Maybe related to the clutch hub locating circlip behind the drum. Ten thousanths inch of change in the width is about all that would be possible before the drum failed from too much heat.
5. If your cluch center is badley grooved by the plates then this will happen when a new basket is installed and the clutch plates no longer center on the old worn grooves. A new center will be needed.
6. The clutch should work fine with the primary vented or sealed. I have installed and used them both ways. Jim

pvisseriii said:

I purchased a "belt" drive kit a while back and have installed it with some issues.

1. The engine sprocket never gets “set” on the crank. Gets pretty close to the cases but works ok.

2. The button headed bolts on the back of the clutch basket needed to be ground down as to not rub on the inner of the inner primary. Works OK now.

3. One inch up and down play needs to be obtained to compensate for the swelling of the Anodized Aluminum clutch basket. This is “almost achievable but the gearbox is at the limit of adjustment in the cradle. Stock belt with kit too short?

4. Due to the extreme amount of swelling of the clutch basket when hot, I lose clutch function. The adjustment at the lever disappears and I have to screw out the handlebar adjuster on the fly to actuate clutch.

5. Also I believe the clutch basket swells to such an extent that it is possibly binding the drivers causing the clutch to drag at stop lights and make it impossible to find neutral and causes hard shifting. Once cooled down, all returns to smooth operation.

My primary is opened up quite a bit for air flow.

I am not sure what size a stock belt would be, but this one appears to be too short.

Any suggestions that would help with these problems would be truly appreciated.

Thank you,
Peter

Click to expand...

Peter,

Did you get the left side primary adjuster kit from RGM? It has some reliefs ground in the bolt section that are there to give you a little extra room. They are a pretty good idea in any case with a belt.

bpatton said:

Peter,

Did you get the left side primary adjuster kit from RGM? It has some reliefs ground in the bolt section that are there to give you a little extra room. They are a pretty good idea in any case with a belt.

Click to expand...

Left hand adj. in place.

comnoz" wrote 1 .Common problem, sometimes I have needed to remove a bit of material from the backside of the engine sprocket center to keep it from touching the cases. Beyond that I have not seen failures there.
AOK
2. Sounds like maybe the clutch locating snapring is not holding or you need to add washers to move the clutch hub away from the inner or move the inner back if the stud in the center of the rear cover is holding it out too far.
If CL snapring not holding, there would be a whole lot more issue than a swelling basket. Adding shims is possible though.3. If you have 3/4 inch with your foot on the rear drive chain you have enough play. Otherwise you may have to file the slot so the trans can move forward a little farther. The next size larger belt is a lot larger and will not work.
From what I have seen the next size belt is 30mm longer. I see no problem there.
4. Swelling of the clutch drum can not be enough to affect the clutch dissengagement. One would think.Something else must be happening. Maybe related to the clutch hub locating circlip behind the drum. Ten thousanths inch of change in the width is about all that would be possible before the drum failed from too much heat.
The out side of this basket swells alot. Why is it getting so hot?

I will venture into shimming basket out a little. But I gotta say, that thing swells.
5. If your cluch center is badley grooved by the plates then this will happen when a new basket is installed and the clutch plates no longer center on the old worn grooves. A new center will be needed.
Clutch center perfect.

6. The clutch should work fine with the primary vented or sealed. I have installed and used them both ways. Jim

I agree.

If your belt is too tight that would be a reason for the drum getting too hot. If the drum is getting too hot then it would make the belt even tighter and the pull from the belt could load the drum enough to cause dissengagement problems. Keep in mind the belt will not stretch as much as a chain and if it is gets tight it will destroy bushings, bearings and shafts. Jim

PS every bike is different but I have tried the next size larger belt and found there was not enough adjustment to the rear . Not to say it couldn't work on yours. Jim

I tore up few belts and bent shafts to nail down optimal rule of
thumb 920 length belt tension.
A 90' twist in bottom run with just short of finger pain effort.
This also allows belt to be worked on-off pulleys by just finger
and blunt tool pressing around.

A 920 count belt on 36T drive to 72T driven pulley should
have pulleys centers at 9.433 inches 239.6 mm.

Thanks to keith1069's, the reference chart is online to view.
http://s424.photobucket.com/albums/pp32 ... 001-1.jpg&

Here's Peel's with cut out for Steve Maney out rigger bearing support.
http://rides.webshots.com/photo/2035489 ... 1179vgldGs


hobot

Hi PV,
You said, "the pulley never gets set on the crank". I found that to be true when I installed my belt drive. I ended up filing the crankshaft woodruff key a little shorter as I believed it was interfering with a complete fit (I was also not impressed with the depth of the taper cut into the pulley, although it has not been a problem). After filing down the woodruff key I noted that the pulley did indeed run very close to the case. As I remember I ended up grinding off a little material near the bottom of the three bossed up areas that support the stator winding. Are all these unspecified "minor" adjustments what the British refer to as "fettling" ???

GB

I ran snot out of Al belt clutch basket and it was everyting the ads
claimed.
I had to learn the hard way tearing up belts, what tension is optimal.
A full 90' twist slack, just short of painful finger effort, in bottom run.
Correct tension will also allow one to just work belt on - off
by finger and blunt tool pushing edges.

The thermal tensioning must be the whole engine and cradle
as this effects triplex chain as much as a less forgiving belt.

I've tried one size shorter belt - it just will fit with gearbox
full forward, but can make rear chain too tense.

hobot