RGM Diaphragm clutch spring compressor

Hi
Can anybody that owns the RGM diaphragm spring compressor please let me know what the set up is? I must be missing something here. Thanks

I'll go look at mine. It is more or less pre set for where it works. It is a heavy hunk.

Don't be intimidated by it. I would be extremely difficult to break it or the spring.

Roger should have included printed instructions on a narrow strip of paper. It does work if setup like he says to do it.

Thread the large nut on the bolt before starting the bolt. Run the large nut up toward the head of the bolt, then thread the bolt into the compressor far enough to work with the thinner locking nuts. Skinny nut on last. Lock the nuts so you have 1/4" of bolt from tip to the thinner nuts locked together. Thread the bolt into the adjuster housing until the thin nuts hit the adjuster. Compress the spring with the larger nut above the compressor. You are basically pulling the center toward you until the spring spins freely.

Belt setup: Advice to put a 90 degree twist in that AT10 polyurethane belt is useless advice. It won't work if you can get a 90 degree twist in it. It will slip on the crank pully and clutch basket gears. Read what Roger has to say about setting up the belt. You want it setup so that it just stops slipping when kicking it over.

Here's a pic:

Thanks Schwany. I had to pull the gears out of my gearbox to access the cam and quadrant. Apparently when I rebuilt it 6 months ago I screwed it up and had to jump back in and fix the problem. Quadrant was set wrong. I learned the hard way. Not sure what you mean by a 90 degree twist? Prior to taking it apart I did square up the pulley with the clutch basket using two squares. Is that what you mean?

jms said:

Thanks Schwany. I had to pull the gears out of my gearbox to access the cam and quadrant. Apparently when I rebuilt it 6 months ago I screwed it up and had to jump back in and fix the problem. Quadrant was set wrong. I learned the hard way. Not sure what you mean by a 90 degree twist? Prior to taking it apart I did square up the pulley with the clutch basket using two squares. Is that what you mean?

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I had a feeling you were going to be taking the gearbox apart.

I'm referring to the belt tension adjustment for an AT10 poly urethane belt that RGM uses in their belt clutches, not the crank shaft and gearbox shaft (basket) alignment. If you have it all under control, ignore the 90-degree twist of the belt reference.

jms said:

Hi
Can anybody that owns the RGM diaphragm spring compressor please let me know what the set up is? I must be missing something here. Thanks

Click to expand...

Schwany,

jms said:

Hi
Can anybody that owns the RGM diaphragm spring compressor please let me know what the set up is? I must be missing something here. Thanks

Click to expand...

Schwany
Got everything back together and put it in neutral and kicked through. Glad you reminded me to check belt alignment. Low and behold the belt walked towards the inside of the clutch basket and I was thinking I was perfectly square

jms said:

Schwany,

Schwany
Got everything back together and put it in neutral and kicked through. Glad you reminded me to check belt alignment. Low and behold the belt walked towards the inside of the clutch basket and I was thinking I was perfectly square

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Also didn't really realize this until today but where the RGM description of the Pre Commando belt drive kit says the belt is 20 mm wide what I received is 25mm wide. It is what I think is the AT10 red belt which was supposed to be 30% stronger than the old. Not sure what the old was. Interestingly my engine pulley is 27 MM wide so there seems to be room for the belt but less room for error. may clutch basket is 35mm wide and when I kick the engine through in neutral the belt seems to travel right in the middle of the basket leaving approx 5mm of exposed basket on either side of the belt. At the moment the belt has about 1" of up and down (total of up and down movement) cold with the engine not running.

All the belts RGM uses are AT10, but yes the Red Continental Synchroflex AT10 belt is supposed to be better. They will shred if too tight or suddenly get too loose even with the so called better spec.

Checked my belt, and it is right at 1" total up and down.

My clutch is noisy at idle when the belt is set where I have it. It gets quieter when the RPMs are up. Could just be how mine is. First run after installing the RGM clutch the belt was too tight, but ran much quieter. I've also run it too loose using the wrong advice, and it will bunch up in the primary against the primary case. That is really not good.

The 27mm crank pulley is what you want. 25mm belt is good for an old Norton twin. A 30mm belt is what many Commandos use. cNw uses a 21mm belt, but it is a different very strong composition and not an AT10 belt. I'm using a 25mm Red AT10 belt like yours. I have not busted it yet.

Schwany said:

All the belts RGM uses are AT10, but yes the Red Continental Synchroflex AT10 belt is supposed to be better. They will shred if too tight or suddenly get too loose even with the so called better spec.

Checked my belt, and it is right at 1" total up and down.

My clutch is noisy at idle when the belt is set where I have it. It gets quieter when the RPMs are up. Could just be how mine is. First run after installing the RGM clutch the belt was too tight, but ran much quieter. I've also run it too loose using the wrong advice, and it will bunch up in the primary against the primary case. That is really not good.

The 27mm crank pulley is what you want. 25mm belt is good for an old Norton twin. A 30mm belt is what many Commandos use. cNw uses a 21mm belt, but it is a different very strong composition and not an AT10 belt. I'm using a 25mm Red AT10 belt like yours. I have not busted it yet.

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Good to know. Roger just got back to me ( he doesn’t always) he also said the 25 mm wasn’t a problem and that the belts ALWAYS run to the outside of the engine pulley. I’ve read all of the trouble you had getting to where your at now

jms said:

Good to know. Roger just got back to me ( he doesn’t always) he also said the 25 mm wasn’t a problem and that the belts ALWAYS run to the outside of the engine pulley. I’ve read all of the trouble you had getting to where your at now

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Just reporting on all the crazy mods. Sometimes they work right away sometimes not so much.

If my primary wasn't such a leaker, I never would have changed anything related to the clutch and gearbox. However, once I got started making changes I went all in.

The TTi gearbox is nice. Problems I had with the clutch push rod in the TTi gearbox and making that work with the RGM clutch were unexpected. None of that is an issue using the stock parts.

Schwany said:

Just reporting on all the crazy mods. Sometimes they work right away sometimes not so much.

If my primary wasn't such a leaker, I never would have changed anything related to the clutch and gearbox. However, once I got started making changes I went all in.

The TTi gearbox is nice. Problems I had with the clutch push rod in the TTi gearbox and making that work with the RGM clutch were unexpected. None of that is an issue using the stock parts.

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Yea the leaking part is what convinced me! Finally figured out what you meant by the 90 degree twist. The 1” of play does allow me to do this

jms said:

Yea the leaking part is what convinced me! Finally figured out what you meant by the 90 degree twist. The 1” of play does allow me to do this

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Supposed to be an easy 90 degree twist. You must have a much longer belt if it is easy to do. If I did that, I wouldn't be able to go far with the belt slipping. It would also slip kicking it over.

Have you been out riding yet?

It’s more of a tight twist. Yea mine is a 980. It’s been a labor of love for about a year and a half. Have never started it and it’s still in a room in the house where I built it. Bless my wife’s heart. Because of my knee surgery taking it out and firing it up probably won’t happen till June. I kid her and tell her that I can’t physically get it out of the room and will have to cut a hole through the side of the house. Going to post pictures of the finished project this week

My belt is an 880. I need to remember that when talking about the RGM clutch. I originally had an 890 on it when the AMC gearbox was installed and the belt would slip when using the twist adjust. Slipped at 80 degrees as well. I only use the up and down no slip on kick adjust method.

Good luck with the knee. My knees still both function. Bicycling most of my life helps keep the joints working for me at 74.

jms said:

It’s more of a tight twist. Yea mine is a 980. It’s been a labor of love for about a year and a half. Have never started it and it’s still in a room in the house where I built it. Bless my wife’s heart. Because of my knee surgery taking it out and firing it up probably won’t happen till June. I kid her and tell her that I can’t physically get it out of the room and will have to cut a hole through the side of the house. Going to post pictures of the finished project this week

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I built my Dominator in a side/back room of our house. Bless my wife as well, it only cost me the building of a wall book shelf once I vacated the room. She did have to wait a couple years, though.