Yamaha DT125R '01 - Running Project
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Global pandemic huh? returns to shed
Not been doing alot, just wanted to share some bits.
After 4 years, finally built a proper DTX Brembo Caliper conversion. Threw some Titanium bolts on for some weight saving, and bling.
Custom Bracket and Spacers made, was fun on the old Myford Lathe. Got to force yourself to work in Imperial though...,
Plenty of braking power with Ceramic Pads on a 298mm Disc. To manage the DTR Fork, I've rebuilt them with 15W Oil and 35mm Spring Top Hat spacers, this effectively shortens the spring travel and keeps the spring in its stiffest part of the stroke. It works well enough for me at 70kg.
Could be better, but you can pedal this thing hard into mid corner so it feels pretty sorted for road use.
I've got a USD setup in bits currently, got a set off NOS 1996 YZ250 Forks, if anything, they just look sick.
I will do a Build thread on installing USD forks for the DTR, as I think many people want to do it but are not sure about the parts needed to do so.
Re-mounted my Ignitech CDI with rubber mounts and polished up my bracket, sadly it seems the company has disappeared. I've never had a problem with my unit and this Programmable CDI is the best thing I ever bought for this project.
The spark on this thing is ridiculously good.
I couldn't be bothered to fix my ported 3MB 'P' 134cc Cylinder so i went back to my old 14,000 Mile standard bore 3MB
Cylinder with a TDR unrestricted Head, and it has been so much fun to ride. Just a torqueey reliable DT engine like I remember it when I was 17.QUICK ENOUGH LOL
Been running different carbs for a few years now, and I have to say you couldnt do much better than well Setup Mikuni TM28ss and the 30ss from a WR200 is brilliant for the 125R.., depending on how good you can setup the floats and mixture.
This is the problem with any carburettor using the standard Inlet,
MIKUNI TM28SS - TM30SS - TM32 - TM34SS - KEIHIN PWK36
My favourite so far has been setting up a Mikuni TM34SS from a Aprilia RS250 and Later model RGV250s, (Same engine)
Mainly, the Venturi is angled so the Fuel Bowl remains level. But it has a really effective power jet and has been easy to setup, it works really well with just 125cc, this engine barks and pulls great at Mid-Range too. For me, I pretty happy keeping this engine under 140cc. It's plenty fun.
I'm using a Modified WR200 Inlet with Boyseen DT200R Reeds. Runs good.
I have a 3D printed Airbox to Carb boot I designed, so it's water tight and easier to jet than a Pod Filter.
Currently waiting to print a new filament that has the right Shore Hardness to produce a rubber part like the original. You need a good amount of flex to seat the airbox and carb together.
This has all been paired with old Nikkon Race exhaust, Handmade, Gas welded steel. There is pretty much no info on these.
I bought this from a guy who used it a couple of times and then stored it for 10 years, as far as I know this is the only DT125R Nikkon pipe left in existence. Which is a shame, because this pipe is so much better than the DEP on the road.
I'm going to copy this pipe into Stainless steel and just keep it the way it is because it suites my application so well. Very large expansion pipe aswell, the design is unique.
Will go further into the restoration of it as it's currently covered in BBQ Black paint.
Long term project aye, I've already had my fun.
Keep it real
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@Calum said in SuperDeet125R '01 - Running Project:
@NINJA Sorry, should I have used the "Quote" feature. I was just relaying that @Darty Said it's taken him 4 years and a pandemic to sort his brakes out.
As the saying goes; "Better late than never!!!"
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Welcome to every possibly carb option for a DTR, the darty edition.
Never heard of Nikkon before. Pretty pipe I must add proper phat boi. Also good to see you cracking on at last man -
@Rizboy We fitted a 38mm keihin carb to a 2001 DTR
https://www.youtube.com/watch?v=bOGAEzTaBgI
Just used a heat gun to up the carb boot and reamed out the inlet manifold to suit.
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I am also working on a custom inlet. Very cool inspiration here
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Prototype V4, 3D printed in a TPU at 80A Shore Hardness like the original. This is chemical and UV resistant filament and it's rather tough!
This is the final design for use with a pressure mold.
Concessions need to be made for 3D printing rubber unfortunately, so now I'm using M5 Socket cap bolts and the original flange that's molded in the Airbox as a sealing face, it actually works out to be the most effective alternative. Much like a YZ Airbox will use the same design.
The Airbox is so important when jetting a 2stroke road bike, we need to control the flow of air and have a place to store some also! Induction theory carries on. The area inside is free of interruption and the boot helps to increase the velocity upon entering the carb. I'm hoping to gain more torque down low by using that stock Airbox volume.
The design now minimises any angles greater than 55deg, this means material does not have to be supported as we print. As you can see, this is the optimal version as the rest of the print can completed cleanly as a vertical slice.
Job done,
So much more flexibility with jetting. Measure 69 times, draw it once.
Mikuni TM34ss finally finished.
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