RGA starter clutch

[Magnidec]

Hi everyone,
Can somebody tell me the outside diameter of the contact ring on the starter gear when new please ?
My bike is a 1985 Laverda RGA and the contact surface is worn and uneven. I'm hoping it can be hard chromed and re profiled to the correct size but need the correct diameter when new if someone could help. Eternally grateful for any assistance. Many thanks.

Whilst I’m here, I’m also having considerable difficulty in obtaining springs and plungers for the assembly on the same bike.
Is there a difference between the 180 as advertised, and a 120 version ?
The usual suppliers seem to be all out at present.
Thanks again,
Howard.

 

[Paul Marx]

Are you having problems with the starter clutch linked to the surface of the "contact ring"?
If not, leave it alone.
You'll find springs, plungers and rollers at all the usual places.

Paul

 

[redax5]

what country are you in ?
I have springs/rollers in stock in Brisbane, Aussie
Wolfgang would have same in Canada

 

[Andy]

There’s been several threads on this which you can find with a search, sorry can’t seem to link any… and I recall some talk about chrome etc.
It is possible to measure the maximum and minimum diameter with the rollers at either end of the ramps, and the contact ring needs to be within that. There is room for a small amount of dressing of the contact surface, before it is too small for the rollers. It is good to take the worst of the dents out but no need to go overboard. Although the dents give the springs a hard time, the springs are cheap and easy to replace every 20k or so.
At 30k from new my RGS had a roller range of 48.5-51mm, the ring was 49.5. And broken springs… hence my schedule for spring replacement every 20k

 

[sfcpiet]

Differences between MkI (180° only) and MkII (180 and 120°) types. Springs and plungers common to all, rollers are different. All available from OCT in Germany.

Geographical location would be helpful...

piet

 

[Laverdian]

Howard from Barry, it’s a dead cert he’s from Wales.

 

[martymoose]

Rode through Barry the other day, just near Blayney.

Bought a reconditioned ring from Eades back in the 90's, it lasted a week. Resist the temptation to build up the old one with hard chrome, etc. Tidy it up as others have said, new springs once a year.

 

[breganzane]

Yeah, unfortunately I'm yet to hear of a sucessful repair. Reproduction freewheels are available, though obviously not cheap. As per others, clean it up and fit new small parts and see how it goes.

 

[Magnidec]

Thank you for all your replies guys. Sorry I should have said my location is Wales UK. To Paul Marx it may be contributory I don't know. The surface is slightly worn and what appears to be some flat spots using a mic. To redax5, I’ve tried Wolfgang but he was reluctant to supply as duty and postage would be more than the cost of product and delivery too long with no guarantees. He suggested Europe. Tried Laverda Paradies in Germany but closed. Tried Laverda Scozia Scotland - no stock, tried Webmoto UK - no stock. Last set from Motalia U.K., but minced plungers after one starting attempt. Had the unit refurbed and re assembled by well known and respected Laverda specialist here in U.K. but first attempt to start after re installation (long time turning but wouldn't fire, maybe carb problem) and it started clunking and the screeching again. Stripped it down, surface scored and damaged again, and cover ring buckled and damaged. 3 springs and 4 plungers now in the sump. I think you've all discouraged me from hard chroming , so another set of new parts and another rebuild looks best, if I can get the bits.

 

[Rob]

I used OCT when I needed new sprag clutch parts. Email octeam@gmx.de Phone (from UK)
00 49 02251 970 752
Using the correct springs and plungers is essential for reliable operation.

Cleaning up the housing per your photo may have allowed the rollers to be kicked at an angle which would also explain the buckled cover. Light indentation on the inner housing by the rollers is normal and only the worst ridges need dressing. As you have found tolerances are critical and sadly that means new parts. The previously split ramp ring (for lack of a better term!) may have stretched its housing.

A poor starting engine will add to the strain on the marginal sprag clutch. Try jump starting your battery. Full choke bypasses pretty much everything in the carbs... presumably fresh petrol and new plugs used?

sfcpiet kindly provided me with this advice a few years ago which you may find useful.

Check the inner ring for cracks and/or wear on the ramps where the rollers bear. The housings rarely give problems except when they have been "stretched" by cracked inner rings.

Also compare the driven ring diameter with that of the ramps. Place 2 rollers inside the inner ramp thingy opposite to one another, half-way along the ramps. Measure the inside "diameter" between these rollers. Compare this measurement with the diameter of the driven ring, you should have a difference of at least 0.3-0.5mm, with the ring measurement being greater than that between the rollers. The ring is approx. 49.5mm when new, smallest acceptable diameter is around 48.5mm, any smaller and the clutch will slip.

 

[Paul Marx]

Maybe been posted elsewhere but the purchaser of Slater's stock has done a coming out.
You may find what you need.

Moto Laverda Parts

 

[Reunited Chris]

Hard Chrome is too brittle and will crack under the point load of the rollers.
My fix is to skim the ring in the lathe with a tipped tool and then to make up oversize rollers to make up the difference in dimension of the machined ring. Rollers I've made up from silversteel, hardened and tempered.
I know some will say silversteel is not good and I won't disagree, but hey, it works for me.