All those big bores and your modded 175 sound like an earthquake!!! So cool!!!

The top end has 80 miles on it and I believe the engine is broken in. time to let her eat! wheelies are super easy and it gets to 75 mph pretty quick. I bet if I had the room, this bike would do the Ton which is reach 100 mph or at the very least somewhere in the mid 90 MPH range. I was short shifting the bike.



you can double click the video and it will take you to Youtube and view it in 1080 full screen 60 FPS glory.

for now I scrapped the plans to install the MX400B pipe and focusing on the sleeper pipe.

I repaired a huge hole in the head pipe that rusted through. here is a small video of the repaired pipe installed on the bike.


and here is a video of the stock DT400 pipe installed and I also installed the FMF Turbine Core II silencer. the engine is noisier than the exhaust note.

in this video I also ride the bike. it acts more like a stock DT400 and this pipe killed the revs. I estimate the HP is in the mid to high twenties range. it will only wind out to about 7000 rpm but does not really make power. it goes flat at 6500 and beyond.

Thanks for testing the stock DT400 pipe vs. the Hooker. Wow, so much power to be had in the pipes.

that's no joke there! I found the same thing with the Bassani and the stock expansion chamber on the 1970 RT1M. it totally changed the power curve!

the RT1M has much more power in this case with the stock pipe than it did with the Bassani.

the expansion chamber could either make or break a 2 stroke!

the 1978 DT175 too will get the sleeper pipe treatment soon as well. I get Meis and Enduronut together on this pipe. I hope Enduronut remembers the specs he did on that engine. with the Big One pipe it makes mad power from 6500 to 7800 rpm but the lower part of the power curve is really soft and the engine was ported to make peak power at 8750 rpm.

Will the sleeper pipe improve the low end on your modded 175 as well as match the top end porting. I am learning a lot from your projects and really appreciate it. You may know I am porting my 78 and if I get it right God willing, the pipe will be another issue.

I am hoping it will and have a much longer harder top end charge peaking at 8750. when I tested the bike with a RT180 pipe it had good low end and lower midrange power but it would not rev out like it should.

I am hoping the bike will reach it's fullest potential.

Enduronut had said that in ideal conditions the engine is good for 30 hp with the cylinder he ported.

That will be awesome having 30 ponies on tap. Those 175's are fairly light if I am not mistaken- should go very well.

oh yeah indeed! I need to go on a serious diet for the 175 to haul around for sure. been paying attention to the build Racer Clam is doing on a 1978 DT175.

these bikes have a lot of potential!

I got some updates on the Super DT400. I installed a replacement crankshaft that I can finally tighten down the drive gear on the crank.

I also installed a Barnett Kevlar clutch kit that came with new steels and friction plates and new springs in this kit.

the crankshaft to be installed.

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the Yamabond for the job. I like the new tip on the tube!

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the new Barnett kit.

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