Switching the Exhaust/Inlet on Greaves - HELP

[BulletWallas.com]

I am working on a bike project and had an engineer that came and switched the inlet and exhaust push rods so that it would allow me to have the exhaust at the front to look more like and Enfield Bullet.

But testing it without the motor running as I am not ready to start it, I find that there is still more puff and noise from the rear of the engine than the front. So I am wondering if the switching of the push rods did the needful at all.

My project is nearing completion and the scope is to have a 5 speed left side gear change, using standard 5 plate clutch with Thunderbird clutch casing, with electric start on a standard Bullet frame that ends up looking almost a twin of the latest EFI classic range. Have had a number of engineering issues but the biggy, being these are all behind me now and it is starting to look very nice.

So if there is a way that I can have the exhaust coming directly from the front of the engine and this allowing the round vintage style air filter chamber to be used I would be so pleased to hear if anyone has made this happen.

Thanks and soon hopefully will upload some pictures of the finished machine.

[albertaphil]

Hi there,

I'm a little confused as to what you did to modify your bike, but simply switching the pushrods will not achieve what you want. If you would like to reverse the flow of air through the engine, you will need to get a new camshaft that has the inlet and exhaust lobes swapped in position. Or you could run your engine in the reverse direction...how you would start it, I don't know. But then your oil pump would not be pumping oil, so that would have to be modified as well. And you would have to change your gearbox to get it to turn the wheel in the right direction. As simple as it seems that it should be to make air come in the front of the engine instead of the back, all of the associated components are integral to the engine design.

Phil

[andrewaust]

Yeah that has got me stumped too Did he somehow cross the push-rods "Couldn't even imagine being able to do that - doesn't the greaves engines have separate push-rod tubes?" even if you could, you would have to lengthen and somehow strengthen the rods due to side loading. Not advisable in any case.

As Phil has stated, the only other practical way would require a complete regrind of a new manufactured camshaft to alter the valve timing for the reverse flow, then you have to check to see if the valves are both the same size and that the engine hasn't got an enclosed breather hole from the head to inlet port as the L100 clones have. Reversing it would pump exhaust gas into the engine.

I'm guessing the engine still runs the same way == more questions.

Lots of questions with this modification.

A

[BulletWallas.com]

I have achieved the desired result and the bike runs well.

Take a look at the red Baron http://www.facebook.com/album.php?aid=2 ... 7189674803

Thanks

[smokyjoe]

Beautiful machine, well done.

[BulletWallas.com]

Thank you Smokeyjoe,

Next time I will use the Lomdardini, has to be better than the Greaves. But this was certainly special in its own way. Wish we had the tools and materials available to have more control over the work here in Delhi.

[coachgeo]

Did you do the valve swapping thing or did you do a magic curved exhaust job?