www.kevinbreedonracing.co.uk might be able to help if you know the size of rings you want. They do a variety of off-the-shelf pattern rings of all types and various sizes.
My bet would be that something has been done to upset the run or seating of the throttle cable while the bike was being worked on. Check the cable is not snagged anywhere along its length and that it's seated properly at the twistgrip and carburettor. Also check the top of the carburettor has been fitted correctly (can't remember if the Beta uses a threaded, screw-on top or the type attached with two screws. If the latter the top should be attached with the cable slightly forward of centre - it's possible to fit it back to front in error) and that the twistgrip is not binding on the end of the handlebar. As mentioned above, when you let the throttle snap shut it should do so instantly, not gradually, and you should hear the "clack" of the slide bottoming in the carburettor. Check these last two points with the handlebars on both left and right lock.
Trouble is Simon, your also falling into the trap of ignoring practical use. In your example, the curved arm would be better if it gave greater clearance to the bottom of the fork leg, allowing greater travel than a straight unit. Now if you wish to be pedantic, you will ignore the minor details such as this. Yamaha front drums suffered from this !!
Yes, sure, I should've noted that there was a reason for curved arms, ie clearance for forks or end of swinging arm. It doesn't impact on the point which started this thread, just included it as an aside.
This reminds me of a debate that went on in Motor Cycle weekly some decades ago about the relative effectiveness of a curved brake arm and a straight one. The theory was that an arm made in an arc shape between the pivot point and the cable attachment provided more leverage than one which was straight. I think the theory was debunked by the technical gurus of the day.
I've got a question about sprockets. Now i've always believed that ideally you should have an odd number and an even number i.e. 11 tooth gearbox and 42 back wheel to ensure wear was more even on both sprockets. However the std combination is 11 gearbox 41 rear wheel. Wouldn't this wear the sprocket unevenly. Alternatively have i had it wrong all these years or doesn't it matter any more ?
I suspect I've been around trials about as long as you have but I've never heard the theory about odd/even sprocket wearing less quickly. I can"t figure out why that would be the case.
Shirty seems to be concentrating on his offroad clothing business. He sent me an email today advertising trials shirts and jeans at keen prices, not keen enough to persuade me into such lurid designs though.
Monty 348 brake shoes
in Montesa
Posted · Edited by cleanorbust
Villiers Services for a superior result. Price on a par with other recommendation.
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