R100 Bean can Mod ????

[BOB UK]

Hi All
It must be that time of year just getting a few jobs done on the R100 Para lever

I’m rebuilding my old failed Bean Can I’ve put a new Hall Effect switch in it that I got from eBay

You have to mod it a bit but it’s not that difficult

I seem to remember a few years ago there was talk of a mod to the advance retard unit that restricted the amount of advance so you got better low speed acceleration

Can anyone remember how to do it or point me in the direction of a site with it on I’ve tried a search but came up with nothing

Thanks Bob

 

[Rob Farmer]

Bob,

The mod you're talking about was generally for heads that were running twin plugs. The idea was to bend the "ears" that limit the mechanical advance and retard unit, you also needed to retard the ignition by one tooth on the flywheel. The idea being that the faster flame front generated with twin plugs needed less advance at lower rom but more at the top end where the increased flame front made it less efficient. To be honest after spending days fanning about with a twin plugged engine I gave up, set it back to standard and just ride it.
I've never heard of anybody managing to set them up right by bending ears. Boyer do an electronic conversion for a twin plug a much easier solution.

 

[BOB UK]

Hi Rob
Thanks for getting back to me

I’ll just put it back together as it is then

What I did with the last one was then to fit it on the bike and run it for a few 100 miles just to make sure it works ok then swop them back over then stuff it under the seat until needed

The last one played up on and off for about 500 mills before it failed it would run fine then cut out and as soon as you started to look for the fault would then re start

It would also randomly misfire but after it let me down I fitted the rebuilt bean can all was back to sweetness and light

I just thought I might as well rebuild the old one so I have a spare