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Took me a while to get the scoot running good . No sense in worrying about sliders and rollers if the engine isn't even running good. Had to adjust valves and drill a vacuum fitting out that was restricted I believe. I did something right because it runs right again. Anyway, I have the variator cover off and the the variator marked real good. It doe's seem to have a weak spring on the clutch to. I can move it in and out fairly easy. Should it be like that ? A stronger spring would give me real good take off and low speed power. But I don't want it to keep my variator from letting my belt go all the way out either at top speed. But one thing at a time. First the variator check.

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Good to here somebody had some sense for a change when designing the Vespa Rockynv. BTW, The Linhia manual says 0.08mm-0.10mm intake valve clearance, 0.16mm-0.20mm for exhaust valve clearance. Translation for us Yanks is .003 inch -.004 intake , .006 -.008 inch for Exhaust . No wonder us Linhai engine driven scooter guys and gals have to adjust our exhaust valves so often. The typical valve clearance specified by your friendly neighborhood scooter mechanic is .005 - .006 of an inch. for the exhaust. Couple that with the inferior valve seats that recede as miles go by and you have to adjust the exhaust valve sometimes every 500-1500 miles. That is " WAY TO MUCH WORK " To have the privilege of riding a scooter around. Especially with all the body work that needs to be removed to do it. So turns out it is perfectly OK the adjust your exhaust valve out to .008 inch clearance. This should maybe double your ride time before it starts stalling at stops needing the valves adjusted again.     PS I have a JCL MP 250 A just like a Roketa-54 (Linhai engine) scooter and I have made removable access panels so I don't have to take my whole scooter apart to adjust my valves. Just turned a 2 day job into an hour and a half. Working on and off of course on the 2 day thing. Best thing I ever did !

While I'm waiting for my fuel pump I'm making a trap door to get to my intake valve easy. I made one years ago to get to the exhaust valve. These Linhia's with receding valve seats (exhaust valve mainly) need valve adjustments often. And since the engine lays down the exhaust valve is accessible from the belly and the intake has to be accessible from under the seat. If you don't make these access doors or holes you would have to take off all the body work just to get to the top and bottom of the cylinder head to adjust the valves. The trick is to make these mods as invisible as possible. We wouldn't want to louse up the beautiful lines of a Reflex clone would we .

I thought you said this 32 mm carb wasn't going to work ? Now I take it off and go back to stock carb, stock 115 main jet now you tell me I should have experimented with the 32mm carb. After you said that I didn't want to waste my time trying to tweak something that wouldn't tweak. And I am still having a hard time trying to find a vacuum fuel pump that will pump sufficient fuel. My float bowl keeps running empty. I finally got a Chinese Jin Bo brand vacuum fuel pump just like the one that just lasted 7 + yrs. on it. Ordered it on Ebay tonight.

I went to put on my old carb on today to get ready to do the variator test. What a BEACH working through that hole underneath the seat. Especially when I'm not using pod air filter (K&N style). When I finally get it in there and all hooked up I try to start it. Gas started coming out of the overflow tube as fast as the fuel pump would pump it. I guess all that wresting with the carb somehow got the float stuck inside the float bowl is all I could figure. Tomorrow's another day

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I feel I should cap this 32 mm carb fiasco off with this. Get this, After all this I put my 115 main out of my old Jap 30 mm carb in the new 32 mm , New carb ran great then ! But no better readings from the tach and speedo than my old carb. I think it had a sleight edge on my old carb in the mid range. But not enough difference to change much. So what that means is if they will take this 32 mm back I want a refund. And the old Jap 30 mm goes right back on with no more than one jet size higher or lower than stock. , It might even run the best with this 115 main jet it came with. Now off to the slider subject I guess .

Aug 9 2016 at 6:10pm jct842 said:
First thing I would look at is the rpm at the top speed you get now. Depending on if it is wound out or not to decide on what weights you have and what you need to go to. If you don't have a tach get one on there. If you are a whole lot under red line you need to go lighter in weights which is what I would suspect.

Doubt if you will be happy with a larger carb with out doing other mods to go with it. Jetting is usually all that is needed.

Folks, Take jct842's post to heart ! And do not buy a 32mm (BS) more like 31mm racing carb they call it. The one I got has at least a 125 main jet which is way to big unless you are gonna mod the rest of the breathing system and maybe even port and cam it. Just do what he says. Don't be a Hard head like me.


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