busy engine

1608 · Post by **1608** » Mon Apr 19, 2010 7:11 pm

I want to up the gearing just a tad on my G12 DL.The Book lists a 17 tooth sprcket for the gear box for the CSR.I know the CSR has a bit more power, but considering most of my biking will be in top gear thought I'd give it a try.It would be much simpler to replace the engine sprocket than the g/box sprocket.Anybody have any observations to make on this please.

alanjennings · Post by **alanjennings** » Mon Apr 19, 2010 7:23 pm

Yes, gear it up, they are "buzy!'-my model 20 is sooo much better now! But I had to change the gearbox sprocket-as an engine sprocket was not available!

GOLDSTAR · Post by **GOLDSTAR** » Mon Apr 19, 2010 7:53 pm

somewhere on the forum there has been an aussie member speaking of using different sprockets for all sorts of m/cycles, I recall asking him where he obtained them and the reply was ' through sprocket suppliers on the internet' do'nt be afraid to have a look and if neccessary to sweat one onto a turned off blank, kind regards

Stan Palmer · Post by **Stan Palmer** » Mon Apr 19, 2010 9:06 pm

There is an 18 and a 21 tooth for twin on ebay at the moment. I was looking for a 21 tooth single for the same reason !
Stan

ajscomboman · Post by **ajscomboman** » Mon Apr 19, 2010 9:22 pm

The standard engine sprocket on a G12 CSR is 23t not sure if you can get a 24t sprocket (never seen one).

1608 · Post by **1608** » Mon Apr 19, 2010 9:27 pm

Thanks Stan, looks like g/box sprocket is favourite then.I'll have a look on E-bay, but would 18 be too much.

Eric · Post by **Eric** » Mon Apr 19, 2010 9:42 pm

The engine sprocket is the easiest to change but has a dramatic effect. I went up one tooth from standard on my 1960 G9 but it became overgeared and the engine could not rev high enough to get on cam. In fact it would go better in third rather fourth gear. You need the revs to develop the power, a one tooth change at the gearbox is no where near as drastic as the engine and perhaps the best option.

1608 · Post by **1608** » Mon Apr 19, 2010 9:46 pm

Thanks Eric.I'm not looking for great speed, just a more comfortable cruising.It would appear that there are 17 and 18 tooth available.Would 18 be too much of a jump, even on the g/box.

wilko · Post by **wilko** » Mon Apr 19, 2010 10:32 pm

I have a 24 tooth engine sprocket on my 650 with 16 tooth g/box and it's still too busy for me! I have just fitted a 23 tooth engine sprocket to my '50 ironhead and it's fantastic, i can sit on 70mph with 60 per revs! But i am a 10 stone weakling! I had a mate turn down the original and welded a new one on.

wilko · Post by **wilko** » Mon Apr 19, 2010 10:34 pm

By the way, the 650 sprocket was an original one but i've never seen them listed? It was a police motor tho'.