2001? Yzf 426 stroked complete resto

63 replies to this topic
  • Nick H

Posted September 07, 2014 - 12:31 PM


Hi all, New member here. Completly restoring a yzf426 I bought a few months ago. Let me know what you think. Work done so far : powder coated frame, New wheel bearings all around, new swing arm bearings/mono shock linkage rebuild kit(bought but yet to install), new tag triple clamps, new handlebars, new grips, new oversize radiators/blue hosing,new seat cover, new chain guide, all new skidplates(yet to install) jetting kit(yet to instal),new hot start lever, new air filter,all new plastics and decal kit, sandblasted subframe, motor stroked by gt thunder. New cylinder, new high compression piston, hot arms with auto decomp. There's more but I'm tired of typing, here's some pics from last month will post current ones soon. Let me know what you think!

  • Nick H

Posted September 07, 2014 - 12:35 PM


Here's a pic.image.jpg

  • -texas2stroker-

Posted September 07, 2014 - 12:39 PM


Bike looks good bud!!! I just got myself a yz426 today!! So far I'm loving it!! Make sure you post pics of engine rebuild. I'm audio is to see inside the engine.

  • Nick H

Posted September 07, 2014 - 12:45 PM


Motors bottom end was done some time ago by gt thunder. Dirt bike shop (Phils Mobile) I bought it off of had it done so I'll only be able to post pics of the top end. Does anyone know how the coil mounts above the engine?

  • grayracer513

Posted September 07, 2014 - 12:46 PM


White frame, eh?

  • Nick H

Posted September 07, 2014 - 12:48 PM


Yup the guys at the powder coating shop call it epoxy white. I think it looks cool.

  • Nick H

Posted September 08, 2014 - 04:18 PM


Could use some information. The crank on my engine was redone by gt thunder roughly five years ago. Bike was never finished or run. local shop picked it up bought lots of parts but never did any work on it other then the cylinder,piston,hot cams and some head work. Now they are telling me the stock timing chain is too short. Part of the deal with me buying the bike is that the engine has to be complete,ready to run and warrantied for two years.is it possible to add a couple of links to the timing chain to make it fit? That's what the shop wants to do.thanks guys.
Forgot to mention it's a stroker.

  • Shawbridge Husky

Posted September 08, 2014 - 05:55 PM


Nice build up, most reliable high strung four stroke out there ! Did you consider doing the 450 body conversion ?
The 450 conversion is what made me decide to keep the bike and invest a little more into it. I've had it like 14 years already, not like I'm losing with it.. Being a machinist mine is going to loose some serious tonnage. The 400 / 426 were overbuilt in a lot of places. The original airbox is crazy heavy compared top to the 450 airbox / subframe unit.

  • grayracer513

Posted September 09, 2014 - 06:39 AM


Where does the mechanic propose to get the extra link(s) from, and the pins?

  • Nick H

Posted September 09, 2014 - 09:48 AM


The mechanic figures he can take links off of one new timing chain and add it to another new timing chain.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted September 09, 2014 - 02:10 PM


Doesn't answer the question of how he plans to close the chain back together.  Would he run it in his? 


How much was it stroked?

  • Nick H

Posted September 09, 2014 - 07:49 PM


I will call him tomorrow to find out exactly how much the engine has been stroked. He told me before it stroked to be 450cc but the googling I have done has pretty much turned up 444cc kits so I'm skeptical. Will reply asap with what I find out. Thank you for your help grayracer.

  • grayracer513

Posted September 10, 2014 - 06:44 AM


Most common stroker cranks are at about the 3mm figure, which would take a stock-bored 426 out to 447.  The 444 kits are big bore kits adding 3mm to the bore size. 


Ordinarily, the 3mm stroke increase needs only a 1.5mm spacer plate under the cylinder, and that normally allows the use of the original cam chain.  Is the shop familiar with the fact that the chain cannot be assembled onto the cams while they are in place in the head, even on stock engines?

  • Nick H

Posted September 17, 2014 - 09:09 PM


Hey guys, sorry it's been so long since my last post. The mechanic at phils mobile was out of town and is due back tomorrow. I'm hoping to get the measurement of total stroke then. In the meantime my new pro taper bars, clutch perch/lever,spark plug boot and new chain tension bolts/nuts came In. The project slowly Marches on . . . .

Attached Thumbnails

  • image.jpg
  • image.jpg

  • Nick H

Posted September 20, 2014 - 04:35 PM


Engine is installed as of today! Things seem to be moving along at a steady pace. Next up is the swing arm. . .

Attached Thumbnails

  • image.jpg

  • Shawbridge Husky

Posted April 27, 2015 - 03:15 PM


Hey Nick, here are the tank pics ! Back in black.

Attached Thumbnails

  • Yamaha 001.jpg
  • Yamaha 002.jpg
  • Yamaha 003.jpg

  • Nick H

Posted May 05, 2015 - 09:29 AM


Hey guys. Changed the swing arm bushings/ seals last night at work with the press. The kit came with two metal spacers that fit inside the seals and two rubber spacers that fit inside the seals.Anyone know which ones go where?

  • Nick H

Posted May 06, 2015 - 12:40 AM


Hi guys.Finished rebuilding the mono shock linkage and shock bushings/bearings tonight.Cleaned all parts and filled swing arm with oil as one chain tensioner bolt is broken off.Ive left it to sit overnight. I also replaced the O rings on the coolant line into the cylinder head and the O rings on the oil return line to stop the respective fluids from leaking out onto the ground instead of staying in the engine where they belong. New kickstart lever is installed as well. I downloaded a manual but it is very vague on the swing arm parts so if anyone has the info on the parts I was asking about it would be much appreciated. Assuming we figure this out I will be installing the rear suspension tomorrow and mounting a chain for the first time. . The ImageUploadedByThumper Talk1430901597.326879.jpg

Attached Thumbnails

  • ImageUploadedByThumper Talk1430901621.807007.jpg

  • Nick H

Posted May 07, 2015 - 08:29 PM


Just rode it for the first time! Rips! Next up is putting on the new gas tank and swing arm logos.
ImageUploadedByThumper Talk1431059375.749806.jpg

  • yzdaddy

Posted May 08, 2015 - 03:11 AM


Your chain looks a little tight

Related Content


Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

Is the 2016 GYTR Yamaha YZ450F too fast? by Fryboy

Dirt Bike   Special Interest Forums   Pro Racing
  • * - - - -
  • Hot  241 replies

yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F

Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies

yz400f throttle bog by yz400fmaniac

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • * * * * *
  • Hot  28 replies

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.