pro circuit exhaust application help!!!

I hate to post a tread about this but I have no choice. I am being offered a screaming deal on a Pro Circuit T-4 WR426 WR 426 EXHAUST FULL SYSTEM. My question and possibly problem is that my bike is a 99 WR400 and i dont know if it will fit. Does anyone know if it will fit my bike? Thanks guys. :thumbsup::bonk::thumbsup::eek::p:bonk:

I think it will fit, same subframe and frame geometry..

Thanks KoKo you make a good point. Anyone know for sure, I have to give the seller an answer by tomorrow??? Thanks

Yes, it will fit!

You are in California, I don't think you understand how loud it is. They are really loud. Is that what you want? Don't you guys have to be the quietest of all?

Don't be eager to buy, you could get it cheaper if you wait. He just wants to get rid of it and is putting the pressure on you.

Matty, maybe you are right. I am in Calif. and my bike is plated. My dual sport buddies would probley frawn upon me if i put that load of a pipe on my bike. The only requirement from the dual sport club is that the bike isnt annoyingly load so people dont call the cops while we are riding and ruin it for the rest of the local groups. It's just so tempting. Less than 100 for the whole set up with the header!!! I guess I have to compromise on the power think to quiet it down a bit and i need to start realizing that. It's just so tempting. I might do it just for the scrambles i run and take it back off, we will see... Once again Matty, I think I will take your advice!!!!!!!!!

what about a stock 1999 YZ 400 pipe, will that make any difference?

what do you think it would do in the performance area for my bike? Anything. :thumbsup:

You can get the procircuit pipe, but to get it quiet, you have to use the 496 endcap (about 1" opening) and quiet core insert (spark arrestor with washer welded in it).

This is a complete contradiction to the pipe, and the performance gains won't be much if any at all.

The YZ pipe is really loud also, you can get a Q2 for your bike, they look good and modern, will make an improvement, and are quiet. I hear that when you match it to a powerbomb header, it makes a nice improvement indeed, all being quiet.

I think you need to think about what you want and what you need. Stick to the stock pipe for now, The procircuit is seriously loud (as well as the YZ pipes) that is why that other bloke is getting rid of it for sure. I have one, but I don't have to worry about noise and no one will hear me anyway.

If you need to be quiet, stick to the stock pipe or Q2 if you want to spend some cash on the old girl.

I think you are better off getting a big bore kit for your bike, They are just as cheap if not cheaper than an exhaust system for you guy's and the performance gain far exceeds that of a pipe upgrade for sure. Your engine is probably getting a bit tired by now anyway.

Now you are talking... What does the big bore kit intail and do i have to set the whole bike up different... Carb, exhaust etc. to handle the upgrade. Thanks again matty

Now you are talking... What does the big bore kit intail and do i have to set the whole bike up different... Carb, exhaust etc. to handle the upgrade. Thanks again matty

Search mate - many people here have upgraded to 420cc's from their 400's. Bigbore kit is usually your old one bored to 94mm and replated, a new piston and rings, and new gaskets that are required. Very cheap.

FSB: 94mm

PISTON KIT: Wiseco #4650P8

GASKET KIT: Cometic #C7401

It would be a great time to throw in a new cam chain as well. Easy to put together yourself, just cam timing and valve clearances would be a bit of a bitch but if you take your time and great care...........

You will have to set the carby up different, more fuel required I would say! Exhaust can stay the same.

Bigbore kits there in USA seem to cost around $300 to $400. Full engine service with new valves and stuff from around $1000.

Have you tried to YZ time the cams in your bike? That is a great performance boost, free too.

Honestly I don't know if it will fit but I had one on my "06"450 and it was a little bit too loud but the performance was awesome. good luck. P.S. the message from matty is dead on I put my stock pipe on when I do a dual-sport ride.

Matty, all the free mods including the yz timing are done. I think I will do the big bore kit in a few months, I think I can yet through the season and then it will need to be done. Thanks for the links and info doesent seem that hard I think I can handle it...

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