A35 top end on a55 bottom? Did I screw up?

So I bought my first moped, what I thought was an a35 engine because of the reed valve top end That was stamped a5. I just noticed the bottom end was stamped a52. Also has much larger transfer ports than the cylinder. (Noticed the ports earlier but not knowing anything it was overlooked) So is this an a55 bottom end? I've already bought an a35 70cc kit and pipe. I am just barely hitting 40 mph, most of the time I am around 38mph with 26 tooth front and 22 tooth rear. I currently have the top end off to fix a base gasket air leak and am waiting on new reed valves to come. Also and running a 75 jet on the stock carb but that will probably have to lower once I get the air leaks fixed. I am hoping fixing the air leaks will help with top speed. I would be happy if I can get up to 45. I really don't want to have to buy another kit if I don't have to. Additional info is the title and Vin say its an 05 targa but all the trim like the faring and side covers said ST so idk what I have. If anyone has any input or help is greatly appreciated.

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Re: A35 top end on a55 bottom? Did I screw up?

Forgot to mention I am running a technigas pipe

Re: A35 top end on a55 bottom? Did I screw up?

Dirty30 Dillon /

There were crossover years where A35 motors had large transfers, but either way it's all interchangeable. Definitely not a deal breaker.

Re: A35 top end on a55 bottom? Did I screw up?

Thanks, so it's probably a35 then? Would the base gasket leak be the cause of low top speed? Should I cut the new gasket to fit the bottom or top end? I was going to use card stock about 1mil thick.

Re: A35 top end on a55 bottom? Did I screw up?

Go to the auto parts store and buy real gasket paper.

Hard to say why it's slow, if you had air leaks then that's part of the problem. Get it all sealed up and re-tune. 75 jet should be pretty close.

Re: A35 top end on a55 bottom? Did I screw up?

Thanks, I will check autozone. I want somthing thicker than what comes in the treats alukit. Because that was a brand new gasket and it never sealed no matter how tight I torqued down on the head. If I went any tighter for sure would have stripped it out

Re: A35 top end on a55 bottom? Did I screw up?

Once u cut the gasket to the case. Use the gasket as a template to open up your small cylinder transfers with a dremel, just ramp them.

Re: A35 top end on a55 bottom? Did I screw up?

Stefan Josheski /

afaik both a5 and a52 is same as a35

Re: A35 top end on a55 bottom? Did I screw up?

Make sure you have some larger jets. I know I have a 70cc kit with reeds and a 15 Sha that I'm running an 85 in right now. 75 just seems smallish for a 70cc reed setup.

Re: A35 top end on a55 bottom? Did I screw up?

> Jay Rivett wrote:

> -------------------------------------------------------

> Make sure you have some larger jets. I know I have a 70cc kit with

> reeds and a 15 Sha that I'm running an 85 in right now. 75 just seems

> smallish for a 70cc reed setup.

85 seems large imo, i run a 74 in a airsal 44mm with a stock Sha 14:12, but also ran a 72 with the same kit and a 15:15.

Re: A35 top end on a55 bottom? Did I screw up?

I was thinking of doing that but idk , I'd have to buy the dremel also never done that befor. Afraid of ruining it

Re: A35 top end on a55 bottom? Did I screw up?

I had an 80 jet in there but was way too rich. It just 4 stroked the entire time and only got up to 30. 75 seems to run ok I still get some 4 stroking though, once I fix the air leaks I think I will have to down jet it

Re: A35 top end on a55 bottom? Did I screw up?

Don't port anything until you get it running right. It should be able to go 40+ pretty easily. If not, something is wrong and it needs more tuning.

Re: A35 top end on a55 bottom? Did I screw up?

True testament to the fact that every moped is different.

Re: A35 top end on a55 bottom? Did I screw up?

> Jay Rivett wrote:

> -------------------------------------------------------

> True testament to the fact that every moped is different.

if you use the same parts every time, they aren’t.

Re: A35 top end on a55 bottom? Did I screw up?

I know its been a few weeks but I thought I'd give an update. I ended up buying a dremel and matching the transfer ports to the case. Doing that gave me a boost in the low end most noticeable. All the air leaks have been fixed. I have the jet down to a 71. If I go 1 up or down in either direction I loose performance. Right now it's running really good. I still don't get much past 40 on a flat road though. 44 on a long downhill. But I am hitting 40 more frequently now. Definitely getting bigger carb and intake in the future.

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