@tbthegr81 change it mate it's not going to do any harm. Obviously allow it to breathe a bit better with a performance exhaust. Next step maybe go up one on the main jet and a performance air filter but not necessary. The 89 model has a restriction in the exhaust in the form of a small washer/collar in the header fixed with 2 spot welds though after all these years and I presume many owners it's probably been removed by now. I highly recommend the dep exhaust. You need to be doing some serious tuning/porting work to justify a bigger carb.

@oisin There’s only the mount under the seat by the battery and a rubber mount under the oil tank...

@yammieguy I don't have experience with arrow exhaust systems. But I do have a Gianelli which was great for peak power. And a Athena which has more low rpm power, less peak power Now I have a custom one and sounds perfect. And great power all the way

@SpookDog Yamaha? It's factory...

Well i have used giannelli it doesnt have any e markings so i am not sure about he model.

I have a Dep full system on my red Dt, and it's still like new. I am anal in maintaining it though, mainly because I knew it was flaky finish to start with. Not a cheap replacement so you would think they could at least build in some resilience to the finish. Does liven up the engine though.

Often it's said, better to use 100% of his 125 than 10% of his ZX.

Atleast throttle response is little bit better.

DEPs are slightly different. They will fit, but as sound mounts are different. Just get one for the RE/X

@dan28 Just thinking don't just cut straight through the whole thing as the baffle tube inside needs to be an inch or two longer to fit into the end cap of I remember correct

@CalDT125 Great result - learnt something new today

Sparks and flames is all I'm going to say...

It’s a little silly really I don’t see why numbers matter it’s the db that counts and the dt is so quiet even without the muffler

Checked stroke of oil pump and found set at 0.22mm, OK for 3db1 model (0.20 to 0.25mm ), removed shim and Max stroke 0.17mm now, manual says 3rn1 onwards model 0.15 to 0.20. Bike late 89. Didn't seem smoky at all anyway, think running in below 6k for 400 miles left it a bit oily

@Bananper Without seeing a dyno it's hard to actually gauge. Two stroke exhaust pipes work off resonance, fitting a pipe designed for another engine is incredibly unlikely to work as intended. If it does work, then what is likely to be experienced is a shift in power. The WR200 exhaust is designed to produce a particular sound wave at a particular RPM for a particular engine. When that translates to the DTR, it's likely that it's making less power down low, then picks up to an acceptable level. The change from where it makes less power, to more, (I.E. powerband) is likely to be exaggerated, such that the user thinks it's faster. But without a dyno, it really is hard to tell. In other words, stick to an exhaust designed for the engine. As it has been designed to provide optimal results.

I doubt it will make any difference. There's a few slight differences between models but the main reason the pipes are different is the later bikes have a different tank and air scoops that foul the earlier exhausts.

I welded it shut

Can you find the link again, Does not lead to any specific DT on sale.