00 Yz426

4 replies to this topic
  • grips03

Posted October 22, 2005 - 03:55 PM


I own a 00 YZ426 and for the last couple of years I've been getting a popping sound out of the exhaust. I just installed a brand new GYTR Carbon Fiber Titanium Full Exhaust. I still get the popping. I also seem to be overheating a bit, in that the titanium headpipe starts to glow with only a little bit of idling. Can these issue be fixed by changing the jetting? Right now the jetting is stock. Also is it safe to wrap the headpipe with exhaust wrap?


  • moto1020

Posted October 22, 2005 - 08:27 PM


the headpipe will glow red after a short warm up.check plug coloring after riding wo in 2nd gear and shutting off engine without letting it idle

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  • Matt96xr6

Posted October 22, 2005 - 09:42 PM


Make sure you do a search on the 00 426 bikes.

You will need to do the BK mod and update the bike with the 01 clutch and 03 450 exhaust cam. Also install the 01+ Nissin master cylinder up front.

For jetting, I had the same exhuast. Do the BK mod, purchase the JD jet kit and set it up per directions on the blue needle. Then purchase and extended fuel screw and you are set! Bike ran perfect with those settings

  • Pincushion

Posted October 23, 2005 - 08:34 AM


Check for air leaks on the exhaust. Also, whats the position of the fuel screw on the carb? There should'nt be a problem with exhaust wrap on your headpipe. Just make sure its good quality.

I'll second Matt96xr6 on upgrading the front master cylinder. The stock Okebono is a pile of crap. I scored a Cannondale leftover Nissin m/c off ebay for $50 and put on a stainless steel brake line. 200% improvement.

  • grips03

Posted October 25, 2005 - 12:08 PM


When I first got my 00 YZ426 I use to stall when trail riding. I installed a Terry cable 12oz fly wheel weight and Renthal 13T front and 51T rear, now no more stalling problems. In order to change/clean the oil filter I changed my head pipe to high mount White Brothers pipe that allowed access to the oil filter. The WB head pipe has been getting smashed up a bit so I bought a full GYTR exhaust on eBay and swapped the whole thing out. I've change the handlebars for Protapers and Answer top triple clamp, installed Works frame guards, GYTR front rotor guard. Replaced my stock air filter with a Twin Air as the old one was getting nasty. Installed Moose throttle tube and Acerbis hand guards. As far as issues I have with the bike they are idling causing head pipe to glow red, losing coolant due to overheating on 4 hour rides that has a number of slow sections, hard to start sometimes due to drop(s) and the suspension has never been that great, but softening up the front clickers has helped. Now I found this website and it seems like the BK mod (help with bog), blue wire mod (helps with starting), 450 exhaust cam mod (auto compression release), and jetting should have been too. I've not run into the front brake nor clutch being crap yet, but I'm no pro rider either. Do all these mods really work, will the casual trail rider know the difference? I thought my bog issue was due to flywheel wieght being added, am I wrong, should BK be done? Does the blue wire mod really help? I don't mind the current start up procedure, but then again I've been doing it for 5 years and don't know any better.


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