Tomos a35 rebuilt still won't start

Summary : It's 32-45degrees outside when I attempt to start it it's very hard to kick like a new engine. I choke it and kick and nothing.

If I choke and open wide it pops a few times so I change my air fuel ratio with the needle clip I have tried in every spot choked and unchoked checking with wide open throttle and closed trying with starter fluid and without. It won't start but will sometimes attempt before dying.

Engine:

my A35 has been completely rebuilt with new seals, gaskets and bearings. I'm 85% sure I put it back together right. While it was down I cleaned it 100% and replaced the clutch with a jammer, with soft springs.

The engine is running a 70cc airsal kit with aluminum reeds new reed valve gaskets

I am using an NGK B7HS gapped to tomos spec and is producing clear clean spark.

My carburetor died so I replaced it with a mikuni vm20 and an mlm intake I'm running stock jet sizes which I know I'll need to tweek at some point but I only have delarto jets and was hoping I could get it to fire before tuning.

My exhaust is a jamarco Fuego?? And has new a gasket.

My throttle is an aftermarket mashup that can take full advantage of the mikuni slide.

Conclusion: my moped won't start sometimes it backfires after puttering a few times, other times it feels like the Kickstart is stopping it like I'll still have my foot on it and it'll stop the engine. I checked the plug after several different types of starts and when it was caked in Black I reduced the amount of fuel, checked the plug again after attempting to start a few times and it was wet. Also I'm running 32:.

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Re: Tomos a35 rebuilt still won't start

Your text cut out at the end. You're running 32:1 fuel mixture? Generally when you're breaking in, you want to do it with a larger jet size vs using such oil rich fuel. Coupled with a VM20 and you're just running wayyyyy to much fuel / oil. I like breaking in with an SHA carb because it keeps everything dirt simple. After break in I switch to the larger carb and dial that in - can be a pain in the ass, so best not to start doing that until you're working with a running and broken in engine.

What was wrong with your old carb?

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

I'm not sure if it's 32:1, out of my entire wall of text that's the only thing I'm not sure of. I got one bottle of oil the small one, to 1 gallon of gas. I don't have a stock carburetor anymore all I have is mikuni. I don't know if you can tell from the picture but I started off building motorized bicycles they use NT carburetors, which I found out just recently is a dumb down mikuni it just doesn't have any tubes coming off of it.

I know that I'm running way too much fuel with my current setup how do I fix that. Do I move the needle clip up or down. Or maybe you can suggest a jet that I can buy that's in the middle of the thousands of jet sizes that I can get I'm 1000ft above sea level. And my house is 1200ft above seal level.

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

I'm running 50-1.

Re: Tomos a35 rebuilt still won't start

Did you put the woodruff key in correctly?

Re: Tomos a35 rebuilt still won't start

Well that's good that you're running 50-1. Stephen is suggesting your timing may be off, might want to be sure that you have that in order. You've got spark, as long as it's sparking at 1.8mm BTDC it's a fuel problem or there's a leak somewhere. Do you have nice compression? Torqued the head down with a torque wrench?

One thing I like about having pedals, is that once I'm ready to fire for the first time I can use my arms to spin the engine via the pedals lots of times until I get it running. With a kick start you've got to hope you're dialed in correctly and then kick it and hope she fires.

And you're right, new rings on a new kit are not fun to kick over in the cold. Once you're sure you've got timing correct, try turning the choke on completely and leave it on while you kick it 100 times to empty out all the fuel that's trapped in the cylinder. You can adjust the fuel slightly by raising and lowering the needle, but you're probably a few jets off. I don't know if you can adjust that out with just the needle. It would be really great if you could barrow a basic bitch SHA and elbow intake to get it going first. Let us know what happens.

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

My engine didn't have a woodruff key or a slot for one. At first I thought I lost it, but looking at the magneto there's nowhere to put one. So I looked it up on the forums and found out that my taper holds it in. I guess that means that I need to manually time it, but I did Mark it with a sharpie before taking it off and I put it back on at that exact mark so I don't know how it could be off.

Re: Tomos a35 rebuilt still won't start

It's a small round peg, unlike a traditional half moon. Picture below. There should be a small slot on the inside of the flywheel.

Definitely confirm the timing's correct.

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Re: Tomos a35 rebuilt still won't start

♣Slew Foot♣ /

Just had this happen to me.

Wrong dimension thickness in clutchside crank seal. It sux or blows..

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

Mine has a hole where a peg should go, but no keyway to match. Its okay though because my magnet had an arrow I lived it up to that and it died in the first kick. I'm so happy. Now that it's running I can focus on headlights taillights turnsignals brakes flat tires broken speedo bad wiring and of course air fuel tuning.

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

Thanks to everyone for input

Re: Tomos a35 rebuilt still won't start

Get R done.

Re: Tomos a35 rebuilt still won't start

> Austin Dovel wrote:

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

> Thanks to everyone for input

So it was the timing?

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

yes. I lined it up* and it *started in the first kick sorry for my auto correct.

I fully expect with the taper and no keyway for it to come out of time eventually but for now its good.

Re: Tomos a35 rebuilt still won't start

♣Slew Foot♣ /

Cigarette rolling paper red loctite wrap paper around crank soak and reassemble use a heat gun or torch micro.

Only the very center. Next time use heat gun and puller.

Re: Tomos a35 rebuilt still won't start

> Austin Dovel wrote:

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

> yes. I lined it up* and it *started in the first kick sorry for my auto

> correct.

>

> I fully expect with the taper and no keyway for it to come out of time

> eventually but for now its good.

The pin only helps line up the timing is all. If you tightened it up correctly it won't move.

Re: Tomos a35 rebuilt still won't start

Dirty30 Dillon /

> Austin Dovel wrote:

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

> yes. I lined it up* and it *started in the first kick sorry for my auto

> correct.

>

> I fully expect with the taper and no keyway for it to come out of time

> eventually but for now its good.

The pin is the key. Manually lining it up is not doing you any favors.

Re: Tomos a35 rebuilt still won't start

The flywheel is held to the shaft via clamping force from the flywheel nut. The dowel is only for quick alignment, it is not required. If the nut backs off slightly, the pin will sheer, and does sheer. I am a completionist and recommend using one, but you don't have to.

Red loc-tite and a good impact driver are the necessities to be sure you can depend on it staying and not leaving you stranded.

Re: Tomos a35 rebuilt still won't start

♣Slew Foot♣ /

The rolling paper mushed fills the keyway... Kinda like the locator pin or a fake woodruff.

Re: Tomos a35 rebuilt still won't start

Austin Dovel /

eitherway it runs. i got it air fuel tuned close toay its running good enough to start jetting.

Re: Tomos a35 rebuilt still won't start

> Austin Dovel wrote:

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

> eitherway it runs. i got it air fuel tuned close toay its running good

> enough to start jetting.

You've been working on this for a long time! So glad you made it to the next level.

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