Are all the Chinese Solexs the same?

[Greybeard]

Grabed one off e-bay when the Canadian Seller listed two at auction. Got the 1st one for a buck and a quarter. I figured I'd probably get one thats been sitting in a warehouse forever.
Took it out of the box today. No decals. Looked in the tank, looks brand new and clean. Main cover says S4800. The wiring looked good. Kept looking for identification. Found J.H.M. on flywheel.
Is this what everyone calls a Hongdu?

 

[cannonball2]

Yep. I suspect the engines on the resurected Velosolex are a little higher quality than what most of us have, they appear nicer in the Velo photos. The engines we get would not fly on an $1800 MB. Still they are useable power units, some require less than others to set right, maybe even a few nothing at all. As I have posted earlier the original Solex parts fit in assemblies for the most part. I rebuilt my first one with good used original Solex engine internals left from my Solex restoration project. It is a real sweet runner with good power.

 

[Greybeard]

If I recall, you used a solex piston as it had a larger window, and head for higher compression, or did you mill yours?
I got the the thing for a couple purposes, none of which was performance. I have what was my mothers '62 Schwinn that she wanted me to throw away, and in the '50s I had a Travis powered bike. It used a Power Products 1.5hp friction drive on the front wheel.
Having said that about performance, I wish it to be reliable, and run good with a minimum of 4 stroking, so I will tinker.

 

[cannonball2]

I used a Solex piston/rod/cylinder/head. The head is higher compression, one could also mill the HD head. The goal was to get performance equal to a Solex. Sounds like you have read the thread pretty carefully so I wont rehash it. I never did figure out the logic with all the extra gaskets under the base and head which lowers compression also. I think as a minimum I would replace the HD gaskets with Solex originals, and mill the head some. Modding the exhaust as mentioned seems to help also. If it runs to suit you as is go with it. I always felt mine was "holding back". The power increase was very noticeable after the mods. May have been the higher compression head and gaskets as much as anything.

 

[cannonball2]

BTW VeloCruz has the original parts. VeloCruz - Solex Motorbikes

 

[Greybeard]

Thanks for the link. I'm going to be taking a serious look at it as I'm going to detail and paint the thing. Besides your contribution to the thread on these things, I was up in the middle of the night reading Brian Solex's site.
Simple little buggers.