yamaha dt125x

[benjy bwoii]

hello im thinking of buying a dt125x when im 17 and i was thinking of putting a full dep race pipe and a reed block and ive heared the 170cc big bore kits are good does any one know what sort of bhp i could reach.thanks.

[Ariel Badger]

6.73 hp, then it will go bang.
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Bikers make great organ donors, get 115 on your licence today.

[stevo as b4]

If a de-restricted DTX is a true 18bhp at the r/w, and the pipe etc makes it around 20bhp, then i think you'd have to be looking at around 25-26bhp with a 170cc kit. Bear in mind this would put it at maybe 30bhp+ at the crank, so it's pretty good IMO.

There are issue's with fitting a big bore kit to any bike, and if you were hunting every last bhp, then the std carb would be too small, the ignition advance curve would not be ideal, and the pipe volume would be too small. But ignoring all that because it's silly cost to change and optimise every other aspect of the engine to suit the 170cc kit, and i think you'd be impressed with the performance.

Would expect some increase in engine wear and heat created, so it would need more looking after, regular maintainence and probably top end re-building at around 6-7000miles, to be on the safe side.

How much is a 170cc kit for the DT motor?

[benjy bwoii]

cheerz m8 for you help whats the best upgrade carb for a dt125x with a 170cc big bore kit.cheerz m8

[stevo as b4]

All i know is that the Mikuni TM30SS will bolt on to any bikes inlet stub that originally had a VM26/28 carb or TM28 carb. I don't know what size carb would best suit a 170cc kitted DT engine, have never tried it! The TM30 seems to make the KMX125 engine go better, and i'd say a TM32 from an early RGV250 would not be a bad carb to use, if you can get it mounted easily and then tune it to suit.

[That_Hornet]

What do you think the max bhp you could get from a dtx, 170 kit and all the works.

Planning a project and i want to keep it under 33 but as close as possible.

Thanks

Hornet

[G]

Why go for a big-bore DT? From acedotal evidence, something like a KTM EXC will be just as reliable; it also weighs less, has better suspension and even the 125 makes more power than than that.

[Finglonga]

[element]

athena big bore is around £400+, then would need bigger carb, airbox mods to suit, ignition remap blah blah.. would cost an arm and a leg for the sake of a few extra bhp at a big expense of reliablility.. I doubt the crank would last long either so thats major engine rebuilds (not just top ends)..

also get caught with that on a prov license and you will get a spanked ass bigtime.. only takes an accident and the insurance companies get involved.. your insurance = null and you will be up sheet creak without a paddle..

and anyway if your gonna go that far you might aswell find a dt230 lanza and use the engine out of it (engine is the same as a dt125x).. even then you'd need the carb, cdi etc but it would be less hassle and probably cheaper..

also a stage 3 tune at stan stephens is only £150.. wouldnt be that far behind a 170 big bore and would be waaay cheaper


EDIT


£500 for a big bore

https://www.pjme.co.uk/acatalog/Yamaha_DT125R_Engine_Parts_Top_End.html
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04' DT125RE (run-a-bout) // 89' DT125R (rebuilt + supermoto conversion)
SPARES FOR SALE. 2RK TZR // 82 DR125 // DT125R/E .... PM ME...

[chillpill]

ive always wondered what the stage 3 tune includes , im guessing its just mostly a bit of barrel work and the head skimmed or something nothing too fancy