PDA

View Full Version : HMF slip-on ?


Catsgot9
02-01-2003, 04:39 PM
Has anyone put one of these on their 400. The pipe came with a 175 main jet and the instructions said to move the needle to the first clip, did that, cant get past 1/4 throttle without it loading up and dying. My motor is stock, along with the airbox, but I did buy a Pro-Design air system for it. Just a hair better, but I know it can be alot better..:devil
RED121572
02-01-2003, 05:10 PM
TRXMaddness just got one not long ago. Look him up and ask him. He will be more than happy to help you out.
Guy400
02-01-2003, 05:42 PM
I put a HMF slip-on on my cousin's 400EX. We used a DynoJet Stage III kit with the lid removed and a K&N filter with an Outerwear. Jetting was spot on for our 900ft. altitude and the quad runs real strong off the bottom.
bmw500hp
02-02-2003, 08:53 AM
Here's the quote from ATV news "Pipe Shootout. Might be helpful.

HMF Engineering: We just discovered this silencer at the Indianapolis Dealer Expo in February. We weren't able to do a seat-of-the-pants feel, but did dyno it.
We inserted a 148 size Dynojet main jet. (This jet is different than the stock 148 jet. It has a different taper and subsequently creates a different way of measuring, etc.) It produced a nice gain on the bottom end for horsepower and torque. On the top end, the gains were quite small.
RED121572
02-02-2003, 09:47 AM
Originally posted by bmw500hp
Here's the quote from ATV news "Pipe Shootout. Might be helpful.

HMF Engineering: We just discovered this silencer at the Indianapolis Dealer Expo in February. We weren't able to do a seat-of-the-pants feel, but did dyno it.
We inserted a 148 size Dynojet main jet. (This jet is different than the stock 148 jet. It has a different taper and subsequently creates a different way of measuring, etc.) It produced a nice gain on the bottom end for horsepower and torque. On the top end, the gains were quite small.

Thanks for taking the time to give us the info. If you or anyone comes across any dyno sheets with this pipe or anyother pipe, please post it.:D
RED121572
02-02-2003, 09:51 AM
I just found this....
RideRed400StYlE
02-02-2003, 11:19 AM
I have the pipe, and I ran it with a K&N Air filter. I used a 152 main jet. 175 sounds way too big to me, I would try dropping down one jet at a time untill it feels like its running right. I ran it with the 152 and I dropped the clip one notch on the needle. Good Luck!!