ADVrider

Go Back   ADVrider > Bikes > Thumpers
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-21-2014, 03:12 AM   #1
tHEtREV OP
Captain Awesome
 
tHEtREV's Avatar
 
Joined: Apr 2007
Location: Middle Park, Brisbane, Australia
Oddometer: 7,240
Question Wr426 mods for desert racing?

Picked up some WR/YZ426f parts the other day with the plan of fitting a DT/IT400 engine in it after reading a bit about a guy doing it with a 426 and an it490 engine, but after collecting the parts and finding I had a complete WR bottom end I began to reconsider.

I though I was just getting a WR rolling chassis and YZ frame, triple clamps, wheel, swing arm and shock.

My other long term plan was do a couple of races I had always wanted to do, namely the Hattah Desert race (4 hour race around a circuit that is 30 or so Klms from memory) and the Finke desert race (high speed (for some) 230 Klm run one day, and then 230K back the next).

I have an 07 Gas Gas EC250 that I was going to use (simply because I have it and didn't want to add unnecessary cost to doing two events that I will be lucky to afford to get to anyway), but was thinking the WR built specifically for the occasions might be better.

In reality it probably wouldn't make any difference which bike I ran because I'm just going to be one of the slow guys trying to finish the races that they have dreamed about riding in since they were a kid and I doubt I would be riding either of these bikes close to there limit, but I really like the idea of building a bike specifically for the events.

And so here is my question, what mods should I do to the 426 to give me a better chance of finishing?

Other than a fully sick sticker kit.

The engine has a bend con rod, and I will be replacing all the bearings while I have the crank out and inspecting the gearbox.

It is missing the cylinder and head, I was going to get a reco cylinder or a second had one and get it plated, head I was going to get a good second hand one, fit stainless steel valves and YZ cams.

The CDI and all the wiring is also missing, I was toying with the idea of getting a Vortex ignition, but second hand ones don't look to expensive, and is there a difference between the YZ and WR CDI?

And all chassis bearings will be replaced.

What other things do you guys suggest or should I just scrap the idea and get the Gasser set up for it?

Oh and I have about 10 months before the Hattah, and the Finke assault will be another 12 months after that, so I'm not really in a hurry yet.
__________________
tEAM iDIOT.
"Far to the general now, and without great final hope of victory, he has nothing to lose. And it must above all have rabies. For the moment, it dominates this special."
Joan Barreda
tHEtREV is online now   Reply With Quote
Old 09-21-2014, 09:22 AM   #2
Kawidad
Beastly Adventurer
 
Kawidad's Avatar
 
Joined: Jul 2005
Location: Central Coast, Cal
Oddometer: 4,576
The transmissions on these bikes can be the weak points. Go through the tranny with a fine toothed comb. The transmissions aren't all that bad, but guys who do clutch-less shifting tear them apart. Also since there is no cush hub on the rear wheel, tarmac puts a lot of strain on the parts.

Stay with the WR parts, because the gear ratios sound like they'd be better for what you have in mind. The YZ transmission is better for closed course tracks, unless I misinterpret your type of racing, then reverse what I wrote.

Overall, they are really tough bikes that are really well made and should well for what you have in mind.
__________________
Quis custodiet ipsos custodes? - Juvenal
(Who watches the watchers)
Kawidad is offline   Reply With Quote
Old 09-22-2014, 03:21 AM   #3
tHEtREV OP
Captain Awesome
 
tHEtREV's Avatar
 
Joined: Apr 2007
Location: Middle Park, Brisbane, Australia
Oddometer: 7,240
I originally chose it because I thought the only way I could get to race the Finke was ride there and back, and I thought that would involve crossing the Simpson (500+K of sand track through the desert), and I thought is was one of the bikes that could handle it and still be decent of road (and I found it cheap), but once I started looking into it properly, the shortest way is actually accessible by 2wd car so it would be a lot easier to cart the bike.

Otherwise I would have only had my 640 or my KLX to choose from, and I don't think either would be great fun in the race.

But taking the car brings my Gas Gas back into the equation...

I'll be rebuilding the WR regardless, but weather it is worth it for two races I don't know (sounds like fun though).

So anyway, as I said, the gearbox will get a good inspection and bearings replaced.

Is a Vortex CDI worth it, or should I just stick to a standard WR (I can pick a standard up for around $100, but Vortexs are around $300 second hand.

And should I bother with a full exhaust, just go the slip on, or pick up a cheap stock one?
__________________
tEAM iDIOT.
"Far to the general now, and without great final hope of victory, he has nothing to lose. And it must above all have rabies. For the moment, it dominates this special."
Joan Barreda
tHEtREV is online now   Reply With Quote
Old 09-22-2014, 08:25 AM   #4
Kawidad
Beastly Adventurer
 
Kawidad's Avatar
 
Joined: Jul 2005
Location: Central Coast, Cal
Oddometer: 4,576
I don't have any experience with the Vortex, which is why I didn't say anything about it. Personally, I'd just go stock and spend the money on ss valves, forget about Ti, too fiddley. You can get oversized valves with springs and maybe a cam and get more bang for the buck than the ignition.

As to the exhaust. If you stay stock on the engine components, then a good slip on will help. Keeping the stock head pipe will give you a little more off of the bottom, but take away from the WOT performance. For what you have in mind, it go with full monte. Since the bike has been around forever, some good used ones should be easy to find. I personally like FMF stuff, but other companies make good stuff too.
__________________
Quis custodiet ipsos custodes? - Juvenal
(Who watches the watchers)
Kawidad is offline   Reply With Quote
Old 09-23-2014, 02:58 AM   #5
tHEtREV OP
Captain Awesome
 
tHEtREV's Avatar
 
Joined: Apr 2007
Location: Middle Park, Brisbane, Australia
Oddometer: 7,240
Next question.

My stator may be damaged (my fault), YZF 426 fly wheel, stator, CDI, wiring etc seem to be pretty cheap, would going to a lighter flywheel be bad for fastish desert riding (I'm not fast enough to call it racing)?
__________________
tEAM iDIOT.
"Far to the general now, and without great final hope of victory, he has nothing to lose. And it must above all have rabies. For the moment, it dominates this special."
Joan Barreda
tHEtREV is online now   Reply With Quote
Old 09-23-2014, 07:37 AM   #6
Kawidad
Beastly Adventurer
 
Kawidad's Avatar
 
Joined: Jul 2005
Location: Central Coast, Cal
Oddometer: 4,576
Going from memory, which could be dangerous, you can use the YZ stator and just loose the lighting capability. The wiring and other WR stuff should work with the YZ stator. You might also look at a WR450 stator. A lot of the parts from the 400-426-450 interchange, actually, more than you might think and the WR450 is far more plentiful. Most of the changes were to the frame, suspension, appearance items, etc, and not to the engine.
__________________
Quis custodiet ipsos custodes? - Juvenal
(Who watches the watchers)
Kawidad is offline   Reply With Quote
Old 09-24-2014, 12:48 AM   #7
DRjoe
Beastly Adventurer
 
DRjoe's Avatar
 
Joined: Sep 2007
Location: Sunshine coast qld
Oddometer: 4,928
Just buy a dr650
DRjoe is online now   Reply With Quote
Old 09-24-2014, 02:57 AM   #8
tHEtREV OP
Captain Awesome
 
tHEtREV's Avatar
 
Joined: Apr 2007
Location: Middle Park, Brisbane, Australia
Oddometer: 7,240
I don't think I could handle all the power from a 650, I'll stick to the small 426cc bikes until I learn to ride a bit, then I might try the big powerful 650cc bikes.
__________________
tEAM iDIOT.
"Far to the general now, and without great final hope of victory, he has nothing to lose. And it must above all have rabies. For the moment, it dominates this special."
Joan Barreda
tHEtREV is online now   Reply With Quote
Old 09-24-2014, 07:58 AM   #9
Kawidad
Beastly Adventurer
 
Kawidad's Avatar
 
Joined: Jul 2005
Location: Central Coast, Cal
Oddometer: 4,576
Yeah, that's the ticket. Think of the fantastic workout you'll get by hoisting around that extra 100lbs.
__________________
Quis custodiet ipsos custodes? - Juvenal
(Who watches the watchers)
Kawidad is offline   Reply With Quote
Old 09-24-2014, 08:51 AM   #10
iyaoyas98
Bored Silly
 
iyaoyas98's Avatar
 
Joined: Apr 2006
Location: Smyrna, TN
Oddometer: 6,248
Quote:
Originally Posted by tHEtREV View Post
I don't think I could handle all the power from a 650, I'll stick to the small 426cc bikes until I learn to ride a bit, then I might try the big powerful 650cc bikes.
I've had a DR650, and now own a WR426. I think you might have this backwards.
iyaoyas98 is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 02:02 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014