B40F engine running again after 18 years( !!!!!!)

[hoogerbooger]

I think I've just been a bit dumb and ignition not at fault.

tried pre-warning cylinder with air gun and putting a little fuel in cylinder ....with not joy.

found the previous spark plug, put it in.....no joy.

read manual on start up procedure ( ) and thought why have I been holding the valve lifter open a bit. Had mis-remembered the bit on air throttle which I don't have.

Started 1st time with valve not lifted. Sounded healthy (  yes even dummies can get there eventually if they read the bloomin manual  !)

(So is the valve lifter only to help get past the highest compression point before starting ?)

(Am chuffed/releaved...but can't progress to tune etc as I have a very leaky fuel tap and don't want to set fire to bike/garage. When my missus gets back I'm sure she'll be impressed about how much gardening I've done)

[Dabbist]

Congratulations Hoogerbooger. I hope mine starts that easily when I get it back together.

[Phil C]

Well done hoogerbooger!

[Dabbist]

Sorry...and yes, bring it up to compression, hold the decompressor in and push it just over, let the kickstart come back up (release the decompressor) and then hoof it.
On the B40 in particular, the kickstart mechanism isn't designed to cope with kicking straight over compression.
The idea is that starting just past tdc, you pump a lot of energy into the flywheel and that inertia takes it over the next compression.

[AdrianS]

Never used the valve lifter on my B40. The engines are a low compression ratio and I don't feel the need to lift the valve to start.
Also find opening the throttle to perhaps half open, a short press on the carburettor primer and it always starts first kick. The only time I ever have to use any choke is when the temperature is below freezing. I also find it is an easy engine to flood.

[Dabbist]

I used to start my 500 Ariel without it as well. As I said, it's not really there for the riders benefit. It's to save the kickstart mechanism. My personal choice nowadays is to be kind to the engine.

[AdrianS]

There is no mention in using the valve lifter in the owners manual for C15/B40 bikes. It is mentioned when describing the controls but not mentioned at all in the section on starting the bike! It does mention not to rapidly use the kickstart or damage may be caused to the starter mechanism.
When I bought my B40, the valve lifter was not functioning and probably hadn't been for many years. When the engine was stripped and rebuilt the starter mechanism was undamaged. There has been a lot of discussion on the use of the valve lifter ( mainly on the B50 org forum) and there is no concensus of opinions as to use it or not. I agree using it will probably take some pressure of the mechanism I don't personally use it. As said before the compression ratio of 7:1 is low on the B40. The C15 is higher I believe and I don't think it has a valve lifter on it ( I don't thing mine did but it was many years ago when I last had one).

[Dabbist]

You're right Adrian. The C15 didn't have a decompressor, they only fitted them to 350cc and above.
My B40's got an 8.75:1 piston in, but I doubt it'll make much difference.
I seem to remember my habit with the Ariel was to stick it in gear and pull it back against compression. Maybe I've always been a wimp