Drives Pillsbury here on the forum turned me onto pipe builder Gary Braun. 1-612-913-2411. Also Rich of Rich Taylor's Porting recommended him. Pm Rich or call his shop if you really want some power. Really cool dude. 1-702-858-9177 Welcome to the forum brother.

BIg Dog. The air striker carb is stupid ! The vanes only increase the signal a the needle jet and pull more fuel through it and the factory compensates by leaning it out , marketing baloney. When I build ait striker carbs with venturi dividers i grind out the factory vanes . I just did a PWK air striker factory power jet carb for a customer i Bermuda with a 1999 KX 125 ,he was the MX champ there for several years . But any way I removed the power jet system and the air striker vanes and built 6 venturi dividers in it . He called me last week and said it is the best monet he has ever spent on that bike .

Rich

Just an update. The pipe is still being made I've seen pictures of the rolled cone expansion chamber. No stinger or header made yet and it looks cool with many pieces flows really nice from one cone to another and welding is very nice. Also Gary is making a handmade silencer for it. We lost use of the mule so Gary is going to get a 75 dt400 motor for testing. It will take some time I imagine for the finished product. Too bad I ported my motor before trying the pipe, but yah I am in it for the long haul anyhow for dt400 owners and maybe 250.

Sending my pipe and silencer off to Mr. Meis tomorrow! Can't wait to see what improvements it makes yet keeping stock appearance. 1976 DT400C.

I can honestly recommend Dave Meis doing a sleeper pipe if you have a 1975-76 DT400.

It has more torque off the bottom and it has a very good midrange and improved top end power happily revving out to and peaking at 6500 rpm. I really wsh you all were here at my place and I would let you ride it. it is improved not only over the stock pipe but the Hooker pipe as well.

I think the Sleeper pipe plus mild porting and the UFO mod with the venturi divider plates on the stock carb done by Rich would be the bomb.

Pedalcrazy that sure sounds nice. Bet that will work some magic. As far as porting maybe just raising the barrel and dropping the intake while widening the exhaust above transfer opening. I don't know enough about porting to offer much. I am thinking that the directions of the ports has alot to do with low end torque and I know it's old school but yah for a novice like me that is what I would do, also shave the head to reduce the squish clearance to perhaps 40 thou inch, sand the dome to get 145 lbs. I got that number from you bigdog years ago from a post of yours. I would like to try this on my next cylinder. Keeping the exhaust height to transfer port opening the same. Cylinder raised by 3mm. Exhaust widened maybe 69 percent of bore, like an upside down trapezoid. Wide at the top narrowing down to stock width at the bottom. Large radiuses emptying into stock width tunnel. This should preserve torque as much as possible. Like Rich said lower intake as much as possible, again large radius to empty down into the crankcase. I wouldn't widen it, that's just my opinion. A gentleman here did all this and he reported with a custom altered dg pipe he could easily outdrag an rm250 of that era. However he reworked the exhaust opening like an oval, not the trapezoid shape. So we can expect better than rm250 like power raising the cylinder by 3, but with a better shape to the exhaust there could be stronger low end I believe. Also, I will always cut a third hole in the Piston skirt intake side for cooling. With porting I have a little insight, if the engine wants to make power in a little higher rev range than the pipe mod should compliment that, same as with stock ports too. With Gary's pipe I should I hope to be able to tell if It would be good for stock dt's. As of right now I am coming into power later in the rev range so the bike runs out of juice due to the pipe. I basically have an ovalized exhaust, that's how I worked it. Even thou I asked for a pipe for stock dt it should keep the power longer and even add to low end. The low end power is the real test as a mid top end pipe if it takes low end away dt owners would not be happy. If I was to fully port again and I am sure of this I made mistakes I would go all the way for it or yz like power, but yah raising the cylinder may be safest at least to maintain as much low end as possible for a novice like me. Like an It400 but more grunt. I have lost some low end grunt but gained some ponies. But remember this was my first cylinder and I changed the directions of all the ports extremely and like I said probably mistakes and it pulls much harder in the high middle and flattens up top similar to stock, but yah I think dt owners might miss the bottom end, which I am hoping this new pipe adds to bottom, may give 30 ponies at the rear wheel. I think it could because the stock pipe is inefficient in design with jogs, dents, baffling material, bad cones. All this robs the power of the sonic wave inside. I am sure you got the scoop already on the best porting for your application. Thanks bigdog.