DRZ 400 crank bearing failure

Has there been anyone else suffer crank bearing failure on their DRZ's, mine failed on the left hand side behind the flywheel, at over 60mph or 100ks on the open road on a corner, lucky my clutch hand was quick on the job, I suspect with the changes made to improve the bikes power the old bearings called it quits, bit bummed out about it all really as it was going really well right up to the instant it locked up.

Question for the experts, can the 4mm hotrods stroker crank use the standard piston, i.e. is the rod shorter to compensate for the increased stroke, just trying to do everything a bit cheaper, may used my newish piston and std bore for the meantime and rebuild the bottom end with a new crank and ACT gears to keep the costs down, just focus on whats worn out, do the big bore when the funds come in. cheers

Crank bearings are not known for failure on these bikes commonly.. but it happens.

 

Yes the 4mm Hot rods stroker crank can be used with standard piston

Crank bearings are not known for failure on these bikes commonly.. but it happens.

 

Yes the 4mm Hot rods stroker crank can be used with standard piston

Legend, thanks for the advice, I suspect the bike had the old stator bolt or whatever happens on the left side, there is residual damage to the flywheel which I think has been bodgied up to sell the bike, the bearing may have suffered damage when that happened and a period of high speed running yesterday may have been a bit much for it and it failed.  

Just bought a full stroker kit with gaskets and bearings from ATV unlimited, just over $500 bucks US delivered to the land of the long white cloud (NZ), will just use my existing piston and barrel in the meantime, will get a 94mm CW big bore later next year, 424cc should make a difference, now just trying to suss out a deal on ACT gears.

Cylinder head work is recommended

Cylinder head work is recommended

Head has been done with new valves, seals, valve pockets and ports have been cleaned up, the 462 will get rhc big valves and rhc cams etc, this head will do in the meantime, apparently they are good to 50-55 hp out of the box, a 424 wont be anywhere near this, I just want to get the thing going again, this wasn't part of the plan at all.

:thumbsup:

your current pipe, stock valves and 39 fcr will restrict the hp figures.... 

The 462 will get the MRD pipe and 41 fcr kit, my money will only stretch so far at the moment, will do the big bore, big valve head, pipe and carb all at once, I will just focus on setting up a rock solid bottom end with the bearings, seals, crank and gears done, I will Loctite the living shit out of it too, so this wont need to be touched, my bike is my commuter, thank god the scooter is there ready to go, or I would have to try and find a car park around university, which is impossible, but then again yesterdays lock up could have killed me, so a &%$#@!ed motor and a bit of inconvenience is getting off very lightly.

 but then again yesterdays lock up could have killed me, so a &%$#@!ed motor and a bit of inconvenience is getting off very lightly.

 

Yep , rebuilding a mangled body is not the go....you are lucky indeed.....

Sad state of affairs, I want to go for a ride

P1000697.JPG

P1000698.JPG

Sad state of affairs, I want to go for a ride

Question who sells the lightweight flywheels for these, googled Trailtech and it comes up with only speedos and stuff

Sad state of affairs, I want to go for a ride

tut tut should of cleaned the engine first dude!

Question who sells the lightweight flywheels for these, googled Trailtech and it comes up with only speedos and stuff

Trail tech is the only manufacture of a light weight flywheel for the DRZ.

 

They work well when they work.. but QA/QC has been spotty over the years so buyer beware. 

http://www.trailtech.net/stators-flywheels/flywheel-kit-16oz-suzuki-kawasaki

 

EDIT: They seem to produce more working flywheels then not,,, there have only been a few runs that had issue, and to their credit they fixed it.. though all along never admitting there was even an issue..

tut tut should of cleaned the engine first dude!

Cheers for the trail tech advice, the motor is getting completely stripped so cleaning it gains SFA ;-)

My new big bore header just arrived on the courier, a melon collie moment really, heaps bigger than the early E model header that's on the bike now, with some nice size steps in the design, pity I cant try it out on the old setup, say it would have made the difference on the dyno.

Just ordered my ACT gears, attached are some pics of the header, lets say its much bigger than the E header and shorter because it doesn't hang down as low at the front, Im pretty happy with it, and its a good fit to the E muffler joint

Cycleworks Header 1.JPG

Cycleworks Header 2.JPG

Nice!! what make is that header and where did you get it?

Nice!! what make is that header and where did you get it?

A guy in New Zealand makes these, from Lower Hut in the North Island, company is called Cycleworks, makes pipes and mufflers for almost everything, I'm quite happy with it really, should flow heaps.  

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