DT125R ARCHIVE

stillbroke · Guru

will a g reg dt 125r head and barrely fit my 03 ?>

eG x LoGiKzZ · Guru

all barrels should fit, even the tzr 2rk, is it 3mb or 3bn?

stillbroke · Guru

not a clue yet m8 trying to get the carb aswell

Calum122 · Guru

Woa Woa Woa Logik!

I thought we were saying the 3BN DON'T FIT without further modifying the bottom end! See Thread Espcially Later pages!

eG x LoGiKzZ · Guru

that is what i was thinking but wasnt sure, so 3bn barrels do not fit on 3mb bottom ends just to clarify?

Calum122 · Guru

The label 3mb bottom end doesn't exist.

My bottom end is stamped 3bn yet carries a 3mb cylinder.

I reckon I had it sussed on the last page.

In Japan they made DTR's (NOT LC DTR's) since early 1985. DTR's that were made before 1989 had the 3BN cylinder on! After 1988 they come with the 3mb cylinder. That's my theory anyway!

stillbroke · Guru

so is there a definitive answer ? as its really cheap and will solve all my probs

Calum122 · Guru

What cylinder have you got on at the moment is it a 3mb?

So long as you buy the same coded cylinder you'll be fine. The heads are interchangeable.

stillbroke · Guru

yea 3mb

stillbroke · Guru

the bike is 1990 that its from do you reckon it will fit?

Calum122 · Guru

Hmm, suspect mate.

Just ask him. Very easy to find out whether or not it'll fit.

stillbroke · Guru

the conrod for that year shares the same part number as mine does 4FU116510000
so does that mean the stroke will be the same ?

Calum122 · Guru

Apparently according to bradders the con rod will be the same size. Where it is placed on the crank is a different story.

It's all there in that thread I linked you to mate. Just need to read it.

stillbroke · Guru

heard back from the guy and the cylinder and head are 3 mb which my cylinder is the same but its a g reg so doesnt make sense???

DT200R MACCA · BANNED

g reg it would of had more engine changes than owners smile

stillbroke · Guru

its looking good
!

stillbroke · Guru

heres the piccys of the cylinder

-- Edited by stillbroke on Wednesday 30th of January 2013 02:44:14 PM

stillbroke · Guru

cylinder is 3mb bottom end is 3bn the head is also 3mb ?

Calum122 · Guru

All bottom ends have 3bn stamped on them for a reason we haven't figured out yet.

If its a 3mb cylinder then it'll fit. Make sure the bore is in good nick. Make sure that it hasn't been over bored many times and if so has the powervalve been modified! Make sure there is crosshatchong on the bore.

stillbroke · Guru

cheers callum but my bottom end isnt stamped 3bn?

stillbroke · Guru

ignore that i was thinking of the vin hahah

stillbroke · Guru

il post some pics when he sends them for you to have a look at

Calum122 · Guru

Personally I'd have that rebored :/

stillbroke · Guru

would be a shame to as its on a standard ,also whats the deal with the pv? is it locked on this?

eG x LoGiKzZ · Guru

yeah the bore doesnt look in great condition, would probably run but down on power, best to get rebore so everything is fresh, and yeah thats locked, someone on here, tripr i think, is looking for those bits if you are going to put a powervalve servo on

scrimsmustang · DTR Mechanic

All the topends are interchangeable with all the bottom-ends from 88 to 07, IE an 07 RE topend will fit an 88 3DB1........ ! a 94 will fit an 07 etc.............. The 88 3DB1 3BN barrel has a slightly slightly different powervalve to the 89 on 3MB barrel 89 3RN1 and 90 3RN2 are the only models with the 3MB heads fitted but the 3MB barrel was used for years, the RE/X even uses a 3MB barrel. The 3RN1 and 3RN2 models are the most powerfull produced when derestricted so the head must be the best fitted from the factory on a DTR.

All the bottom ends have 3BN stamped on them as a generic model code from 89 88 has 3DB1 as there are that many world wide that use the same crankcases until the change to 4BL in anticipation of the introduction of 17 digit vin numbers