Hitchcocks Forum

Saul on the road to Damascus me! Finally sorted out the issue with the idle on my Bitza. Couldn't work out why it would idle fine when cold but as soon as it warmed up there would be a gradual decline in the strength of the idle. I have the 389 Amal on it and so decided to try a 26mm concentric that I have on the shelf in case there simply wasn't sufficient draw to pull the idle circuit with a 350 pot on an 1 1/8" carb.
Clearly bollocks now I think about it but desperation gets to chap. Anyway the 626 worked fine until the bike was warm and then same issue. Scratching my head I tighten the primary chain which has loosened and begun to clatter and I think ( lightbulb moment) I've put an aluminium barrel on this bike it probably expands differently and maybe the tappets are too tight. Hallelujah I pull off the cover and what do you know the inlet tappet is tight. It now idles like good un and I've put back the 389 and all is well. Trap for young players that one ally barrels mean that you can't assume that the tappets will get looser as the bake warms up the way they did with an iron barrel. Hopefully the inlet valve seat is ok and I won't have to do a valve grind in the near future.

Interesting info Simon, thanks for sharing it.

Yes indeed, that is interesting.. So maybe there is something to be said for checking tappets with engine hot. (Alloy barrel only.) This may be the cure for the traffic light syndrome that haunts many modified
alloy motors... thanks gwilly.

So there I was admiring my lovely machine still ticking over like a chronometer and minus a clank from the loose primary chain. When wouldn't you know it the kickstart return spring breaks! Well I had 24 hrs of motor free troubling!

I will remember your warm engine alloy barrel tappet advice as I too want to upgrade my iron barrel .

Yup... Life gets Tee-Jus dont it.....



http://www.youtube.com/watch?v=2HlEdMg7d_o

Perfect track for my current woes thank you Gwilly. I've ordered the spring and a new kickstart pawl. Knowing the excellent service from our esteemed hosts I should be back on the road in a week even though I'm 12000 miles away from Solihull.

I stayed on the road without a return spring for ages once. The bike was my only transport at thevtime so I just used a bungy strap till I had time to fix it. It was like that for some weeks if I remember.

Hi guys-------- sorry GWILLY, you've got me there, matey !! So what's this "Traffic light syndrome" then ?? PS That "Life gets tedious, don't it??" would have done well for the theme tune to my time in the Civil Service !!

AlanR: Re your request for clarification of `Traffic Light Syndrome`. I`ll tell you again; It`s caused by the Green light sucking the electricity from the bike`s ignition system; you might have noticed that a bike will idle perfectly while the traffic light is Red, but stalls when it turns Green. It also happens to me when waiting in front of fifty Hells Angles blipping their throttles.