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Hrc 260 Kit / Mitani 280 Kit / Lewis 290 Kit

Featured Replies

Does anyone know the performance difference and mapping availability between these kits?Is anyone using any of the above ?

what is the lewis 290 ?

is that aussi spec or do we get them in the uk?

if so how much?

what is the lewis 290 ?

is that aussi spec or do we get them in the uk?

if so how much?

Hi all

I have got a feeling its only in the USA. It

the 290 kit sounds very interesting, but i've never heard about thumper racing. are their products any good?

its a shame that the hrc 260 kit is so expensive, but you just know that it will be brilliant.

is the mitani 280 kit still around? i thought they stop selling that one.

yes ,the mitani 280 is still around and it is in my opinion the best barrel and piston kit available.

it works best with a custom map :guinness:

Thumper Racing is one of the premier four stroke hop up shops in the states, they

make excellent products, and for most brands.

  • Author

Thanks for the replies. Yes the Lewis kit is the Thumper Racing kit , it does seem like great value, but I dont see how it doesnt need re mapping ?

Cheers :guinness:

QUOTE the way I figure it though is the EFI measures what the engine needs and gives it to it, kind of like diffrent elevations

reply . no it does not

  • 4 weeks later...
QUOTE the way I figure it though is the EFI measures what the engine needs and gives it to it, kind of like diffrent elevations

reply . no it does not

now, what I don't understand, is why create a new barrel and piston for just 10cc increase???

does it make much difference ....anyone know ????.........................................................masso

Masso Posted Today, 10:47 AM

QUOTE(munch @ Dec 6 2006, 10:55 AM)

QUOTE the way I figure it though is the EFI measures what the engine needs and gives it to it, kind of like diffrent elevations

reply . no it does not

now, what I don't understand, is why create a new barrel and piston for just 10cc increase???

does it make much difference ....anyone know ????.........................................................masso

That was the 290cc kit we where talking about...+40cc

The HRC kit is only 260cc but has a cam and the two stage mappable EFI, why only 10cc I don't know, maybe that is what works the best for there cam.

apparently the cam alone is what we want!!!....its very torquey

Thumper Racing is one of the premier four stroke hop up shops in the states, they

make excellent products, and for most brands.

:agree:

I had Thumper Racing build an XR280R motor for me, and it was awesome! :icon_rendeer:

  • 4 months later...

Info update,

The Thumper racing kit after testing has down graded to a 272cc because the head would not flow for a 290cc. It is being built for U.S. Montesa.

Since my bike already has about every available option I figured why not get a big bore for it. I got the Mitani 260cc kit that is now available from LewisportUsa which includes a two stage programmable ECU as well as a cam, barrel and piston. It is built to the same specs as the HRC kit. The piston is a two ring design (stock is three ring) and has a different done shape.

The first thing I noticed was the bike defiantly had more snap. After riding a two day trial on it and then a little more at home it will also grunt down at lower RPM's so you can use a higher gear in tighter situations and then still have the snap when you need it. I also let a lower class rider try it on the softer setting and he really liked how it worked in the slow rpm situations. With this kit that has the two stage mapping it works well from novice to expert :thumbup:

Cant really as yet add too much constructive info but ive just got a repsol rep with the 280 kit on it and :( boy does it go!!. Maybe i should start and do supermoto!

Not really had chance to ride the thing as yet, but just going to gear it down and try different maps on it. Im on the single stage unit and think i could do with the 2 stage one and have looney and then 80cc setting :thumbup: Will let you know how it shapes up.

  • 8 months later...

Just to bring this topic back to life......................................

The S3 280 cc kit is now available in the UK,anyone got any plans to get one?

Or has anyone tried the Thumper racing 272 kit??

Benz

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