Tomos 70cc kit questions

I just put a 70 cc kit on my Tomos Sprint and i am pretty dissapointed with te results, i gained a little bit of low end power, but at top speed it is about the same, maybe 1mph faster, i am going to bump up a tooth on the front sprocket to get some more top end, but does anyone know if there is something else i can do, or do these kits just suck?



Ask for Ree!

Ryan,you got to take it easy and let the rings seat before you thrash it.Yeah,with more power you need a bigger front or smaller back sprocket.Your kit came with a bigger jet,right?Well,is your airbox giving it enough air to compensate?Reeperette is our TOMOS expert so maybe he'll answer you.

Re: Tomos 70cc kit questions

what kit is it and where did you get it from?

i have put on many 70cc kits and they have all seemed to produce at least 15mph more. do you have all your cylinder head nuts tight and inlet manifold and carb tight

if you don't it may be leaking and will waste your cylinder

Re: Tomos 70cc kit questions

Sprint Man /

You might have one of the old kits. Recently, my state just got the new kits delivered from Taiwan, and they're in much better quality, and craftmanship. I don't have a speed kit, but I'm gettin a 60cc kit intstalled on the new ped I'm gettin this Christmas. I would do what Ivan said, if there's still a problem, get it checked out at your local moped shop.

Re: Tomos 70cc kit questions

I will check all the bolts, i am sure everything is tight, i know tht it is one of the ne kits that they are not having problems with, i still need to break in the new top end so, im sure i will gain some more speed once i get it broken in. thanks for all the tips though.


Moped Militia

70cc Kits

Reeperette /

I've seen a lot of dissappointment with the kits, both over quality control and performance issues.

If they kit isn't delivering, you check the obvious stuff first, and leakage is common problem - if you're not gettin any serious performance boost that's what I would check, doublecheck, and triple check.

I used to check for leaks by purging the fuel line and blowing smoke into it - if any smoke came out of the carb, manifold, etc, you got a leak somewhere...

Lets also make sure of the parts in question...

70cc head, jug, piston and rings.

15mm Amal Carb with large jet.

Bi-Turbo exhaust.

27tooth sprocket.

Now, if you happen to be missing any of those parts here, no, you will not get serious performance, cause they all take advantage of each other.

In fact, the 70cc cylinder is the least helpful of the above, if you are mounting it solo, the BiTurbo is the most.

Also, bear in mind that a really bad idea is a 70cc Cyl with Biturbo and the original carb and jet....that's like handing a lit bomb to an anarchist...sooner or later, boom.

Also, there's been good results (at least so far) with removing the airbox entire, but the jury is still out on long-term effectiveness of this.

Confirm your parts layout, and let me know.

Oh yeah, and one more thing to check...did any of those pathetically wispy piston rings crack when you put it together ?

That'll happen sometimes too.


Re: 70cc Kits

Hey,Ree!You must drive the Cab on nightshift,eh?I noticed you been posting near 4am sometimes.When you said using the original carb and jet,did you mean that even with a larger jet,it might seize?`Cause see,I have the original carb with a 64 jet instead of a 52 in my Franco-Morini and regular exhaust,but very little resistance to it.I think what caused my soft-seize the other day was my timing was way too fast.My airbox is big and drilled out for volume.What do you think?

Re: 70cc Kits

Reeperette /

Well, what I think isn't nearly as important as the color of your plug after a coupla plug-chops to make sure.

But I've seen two kids seize by using the original carb and a 70cc was a damnfool who left the original jet in there after me telling him how bad an idea that was..(ergo, he deserved what he got..) - and the other did have it rich-jetted, but I suppose it could be a factor.

I do not truly understand the principles of jetting, or even some do, it just looks that way cause I have nearly two decades of practical experience.

Were it me tho, I'd have the larger carb, just to be safe...sezies are damn expensive, especially ones like mine where you lock-seize at 38mph and slide, and then the rear tire explodes and ya dump the 'ped.

I think fred has the piston that happened's way nasty.


Re: Tomos 70cc kit questions

InfectedBootSector /

I hope you didn't mash on it yet.. if ya did, your not breaking it in properly, and you may be screwed anyway... as much of a temptation as it is, the better you take care of the bike during break in, the better it will treat you in return. Pamper that thing for a while...

They arent new kits

They are the SAME ones. No SUCH thing as a new one. THey were ALWAYS made in Taiwan.

Sorry to break it to u.

just check

look at recalls

Re: Tomos 70cc kit questions

dude dude do not get a 60cc kit it is not worth it

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