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By Jools
#2076
Hi again!
This evening I had the bike running perfectly, then 10 mins later I noticed the carb leaking petrol from a hole at the bottom of the float chamber. I'm guessing a sticky valve or float height??

Regards

Jools
By Gwilly
#24300
Hi Jools sounds like it may have been the cause of your throttle response thread..
check that the float hasnt got petrol inside it.. ie leaking. Give it a shake.

check the float valve for crap..
By Alan R
#24311
Hi guys--------- remember that when setting the float height it's measured WITHOUT the float-bowl gasket fitted.. But DO fit it on when replacing the bowl !!---------- Sounds like it's time for a carb. overhaul kit ???
By sofiaspin
#24319
At the risk of being repetitive buy the AMal mk 1 concentric and enjoy much improved performance, running starting etc etc and do away with these tiresome problems!
By Jools
#24327
Hi sofiaspin, I've got one I bought (new) when it was on the road 3 years ago. I Could never get it running right. The bike lacked power especially on full throtle, and I kind of gave up on it.
By Jools
#24329
Just as an update for anyone getting a similair problem, stripped & cleaned carb, re jetted one step lower on main (was 100, now 95) and changed pilot to 27.5 (from 25 I think). Noticed the float height was a 2 - 3 mm low so corrected as per technical notes. Haven't tried it on the road yet but no leak, starts well & ticks over way better than it ever did.
Regards - Jools the happy bunny
By Alan R
#24337
Hi JOOLS---------- glad to hear all's well now BUT (and there's always one, eh ?) --- as you have an open silencer fitted I'd be inclined to put that 100 main jet back in....The change won't have had any effect on the start/idle performance (That'll be the pilot jet plus cleaning and float setting )but for full throttle performance it's better to err on the rich side and use a tad more fuel than have a hot-running engine etc....
By sofiaspin
#24341
Hi Jools good news. Surprised about Amal Mk1 - was it supplied by Hitchcocks? They had mine all set up to match an open exhaust, mind you I had to put a bigger main jet in as there was fuel starvation at 65/70 mph and it cut out on me several times before we worked out the problem. Now utterly sorted.
By Jools
#24356
Thanks Again. Alan - May well do that when I get back on the road and test things out. I changed to a 95 because whenever I did a plug chop, the result was always too rich. Sofiaspin - yes it was from hitchcocks. I suspect it's just a matter of changing the main jet. I've still got it so will eventually get it sorted.

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