ET: Engine (Twin) Engine cutout when the bike leans!

Kevin Emery

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Hello

I have a 52 C series rapide with a strange problem. If I start the machine, kick start only, on the rear centre stand it runs fine. If I push it forward off the stand and then lean it over onto the side stand the engine slows then stops. It does this on either front stand.

So the bike runs in the upright position but lean it either way and the engine stops.

I have recently bought the bike and it has been fitted with brand new carbs.

Any ideas?

Regards
Kevin
 

roy the mechanic

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It would help if you would tell which kind of carbs are fitted. As a rule, as soon as mine starts, I ride it.
 

Nulli Secundus

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Others may disagree, but I think you are expecting a bit too much for it to run on either prop stand.

If you do not like the balancing act of putting the rear stand up whilst the engine is running it might be a good modification to fit a Dave Hill's centre stand, if you do not mind deviating from standard.

By the way it is not good practice to start the bike on the rear stand as the stresses can break the fork ends. Make sure you use the decompressor in the meantime.
 

greg brillus

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If it has the original side bowl carb's, the one opposite to whichever side the bike is leaning will flood somewhat due to the raised float level. This does not happen when you are riding in the same way that the level of water in a bucket remains stable when you spin around in a circle. There is nothing you can do but live with it, as if you alter the float level, you will affect how it runs be it more rich or lean.
 

Kevin Emery

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I have fitted a Dave Hills stand. Now I can kick start it without damaging the forks. Once started I can just roll it forward and ride. Problem sorted.

Thank you all for the advice.
 

erik

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with the Theorie mentioned above a sidecar equipped motorcycle would be impossible to ride on alpine passes.Erik
 

BigEd

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with the Theorie mentioned above a sidecar equipped motorcycle would be impossible to ride on alpine passes.Erik
Greg's statement is correct. A solo motorcycle leans when going around a corner and the fuel level remains the same due to the angle of lean.
A sidecar does not lean and the forces push the fuel in the direction of the outside of the bend when cornering fast. Racing sidecars often use twin float chambers or "swill pots" to combat the keep the fuel level correct.
 

erik

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when i lean my motorcycles on the propstands they Keep on running.and my horex -steib combination with an old bing carb was runnung well even when sharp cornering.regards Erik
 
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