Fixing a seized bike

[motor_mayhem]

"Joyously" my RMZ seized yesterday so I now have to go about unseizing it and getting it going again (or deeming it a write off if the crankshaft is seized, pretty sure it was a water pump failure so new crank + new pump + piston kit + labour = it's history).

Has anyone had to do this before? Are there any gotchas? Obviously I can't move it to the correct TDC to line up the cams as it is stuck solid.

[barty5]

rebuilt plenty of other 4ts only thing to do is strip it and work your way from top to bottom to find the fault. I its a write of in your eyes let me know maybe interested.

[Crasherfromwayback]

"Joyously" my RMZ seized yesterday so I now have to go about unseizing it and getting it going again (or deeming it a write off if the crankshaft is seized, pretty sure it was a water pump failure so new crank + new pump + piston kit + labour = it's history).

Has anyone had to do this before? Are there any gotchas? Obviously I can't move it to the correct TDC to line up the cams as it is stuck solid.

You'd be surprised (if you don't already shop there) how cheaply you can get bits/engines from Ebay for mate.

[F5 Dave]

"Joyously" my RMZ seized yesterday so I now have to go about unseizing it and getting it going again (or deeming it a write off if the crankshaft is seized, pretty sure it was a water pump failure so new crank + new pump + piston kit + labour = it's history).

Has anyone had to do this before? Are there any gotchas? Obviously I can't move it to the correct TDC to line up the cams as it is stuck solid.
Ouch. I'd blame Justin's hillclimbs if you were silly enough to try them.

[motor_mayhem]

Ok so am carefully (slowly) taking the engine apart to see what has gone wrong.

The info so far:

There was definitely plenty of water in the radiator.

There was plenty of oil and when drained there is no flecks of metal in it and nothing visible in the oil filter either.

The cams are spinning freely by themselves.

There seems to be nothing wrong with the water pump, it's not moving as it's still connected to whatever has jammed, and there are no fins broken or anything.

The valves don't seem to be stuck open or anything, though will know for sure when I get the head off.

The one thing there was was an abundance of mud on the radiator. I noted I had missed a spot when cleaning and it was caked up there, which leads me to wonder what it was like when it wasn't clean.
Is it possible that if enough mud was on the radiator, it could cause the engine to overheat? I would think that I would have noticed the heat against my boots from the engine though.

[F5 Dave]

Pull that side cover & see what is locked, could be clutch off & crank will rotate. on not.

[barty5]

My guess will go with crank.
How many hours has it done?

[Jay GTI]

Is it possible that if enough mud was on the radiator, it could cause the engine to overheat? I would think that I would have noticed the heat against my boots from the engine though.

If there is enough mud, it will restrict airflow and cause overheating (hence why some stick sections of old women's tights over the radiators in slimy conditions, to discourage mud from sticking to the rad fins). Also, when I've boiled the Kato, I didn't really feel any increase heat from the engine prior to it boiling.

"Good" used OEM cranks on Ebay from US$60, obviously a risk involved in anything used from overseas sellers, but if you want a cheap fix and it's either that option or sticking the bike out with the recycling...

[Pornstar]

(hence why some stick sections of old women's tights over the radiators in slimy conditions, to discourage mud from sticking to the rad fins)
will young womans tights work the same?

[Crasherfromwayback]

will young womans tights work the same?

Might be too small.

[Jay GTI]

will young womans tights work the same?

Ha ha you've been on form the last couple of days...

...but from back when I was young, free and simple, ooops I mean single, old women's tights were much easier to get (into)...

Plus I find they work better if they are a bit baggy and smell of lavender and wee...

[motor_mayhem]

My guess will go with crank.
How many hours has it done?

If it was the crank, wouldn't you hear some clunking prior to it seizing, or is that only when the bearings are shot?

done 80-90 hours (30 on new piston and rings), the previous person didn't have an hour meter, and 25 since I've had it.



it's either that option or sticking the bike out with the recycling

I have been pondering keeping it and fixing it as a project over the winter. Athena kit perhaps? Still got to see what the damage is yet.

[crfchick]

Gutted to hear about your bike.
FYI if you do rebuild it, but want new parts I got OEM parts from powersportsplus.com and found them to be the cheapest that I could find online. I think they order the parts in and then send them out to you so there was a bit of a delay in getting the bits but I had no hassles with them.

[barty5]

If it was the crank, wouldn't you hear some clunking prior to it seizing, or is that only when the bearings are shot?

done 80-90 hours (30 on new piston and rings), the previous person didn't have an hour meter, and 25 since I've had it.




I have been pondering keeping it and fixing it as a project over the winter. Athena kit perhaps? Still got to see what the damage is yet.

no not all the time our little 65 did the big end bout 6 months back never heard a thing just lost all power although in this case it did still turn over it would be odd for something else to go and cause a complete lock up. Id pull the clutch out next quick and easy to do if its still locked it will be the crank at some point. have you go a work shop manual for it ??? i have a pdf for the 08

[Jay GTI]

have you go a work shop manual for it ??? i have a pdf for the 08

Pretty sure the '06 is still the Kwaka/Suzook bastard child, '07s onwards are a completely different (Suzuki only) animal. Might be some common parts though....

I'd keep it as a winter project if it is a crank issue, the Athena kit would be very cool!

[barty5]

Pretty sure the '06 is still the Kwaka/Suzook bastard child, '07s onwards are a completely different (Suzuki only) animal. Might be some common parts though....

I'd keep it as a winter project if it is a crank issue, the Athena kit would be very cool!

Well if so ive got an 06 kxf pdf wkshop manual as well let me know if you want one of them or both. if they where the still the same as kwakas then they to would have suffered for the on going to smalla radiators that kwakas had form 04 till round 07.

[Crasherfromwayback]

Pretty sure the '06 is still the Kwaka/Suzook bastard child, '07s onwards are a completely different (Suzuki only) animal. Might be some common parts though....

I'd keep it as a winter project if it is a crank issue, the Athena kit would be very cool!

Was a Suzuki as such though anyway...

[Jay GTI]

Well if so ive got an 06 kxf pdf wkshop manual as well let me know if you want one of them or both. if they where the still the same as kwakas then they to would have suffered for the on going to smalla radiators that kwakas had form 04 till round 07.

aaaand just to be a real awkward prick... a quick google confirms my vague memory that Kwaka went for their own in-house developed and quite different 250f in... 2006.

But again, it probably also used the previous collaboration 250f as a basis for development and thus still shares some parts.

[motor_mayhem]

I found an online manual for a KXF250 2004 which is pretty much the same. I gather when Suzuki took it in 06 the only change they made was to increase the radiator size.

[scott411]

the 06 rmz250 is basically the same as the 05 KXf250/rmz250,

the motors in the 06 kawasaki is different, but not a hell of a lot different, the 06 kawasaki went to an allow frame, and bigger radiators,

the 05 had bigger radiators than the 04,

[Pornstar]

jeez your havin a tough time with bikes lately mate.

[Crabby]

the 06 rmz250 is basically the same as the 05 KXf250/rmz250,

the motors in the 06 kawasaki is different, but not a hell of a lot different, the 06 kawasaki went to an allow frame, and bigger radiators,

the 05 had bigger radiators than the 04,


I have an 07 KXF and it has larger radiators than my bro in laws 06 kxf and mates 07 RMZ. In 07 on the KXF they apparently revised the valve stems, new gearbox and bigger radiators, I have a CD here with the workshop manual for the 06 KXF if thats any help.

[gwynfryn]

I have an 07 KXF and it has larger radiators than my bro in laws 06 kxf and mates 07 RMZ. In 07 on the KXF they apparently revised the valve stems, new gearbox and bigger radiators, I have a CD here with the workshop manual for the 06 KXF if thats any help.

Good thing you went for the 07 being a 'plus size' rider.

[motor_mayhem]

I got the spanners out and got the head off and it is definitely a seized crankshaft. The bore looks in reasonable condition so a new piston and rings may suffice but I have yet to decide what to do about it all.

[scott411]

I have an 07 KXF and it has larger radiators than my bro in laws 06 kxf and mates 07 RMZ. In 07 on the KXF they apparently revised the valve stems, new gearbox and bigger radiators, I have a CD here with the workshop manual for the 06 KXF if thats any help.

the whole intake valves are thicker on the 07, and the mod came out as an upgrade half way though 06, (the exhaust valves are the same)

[Rupe]

the whole intake valves are thicker on the 07, and the mod came out as an upgrade half way though 06, (the exhaust valves are the same)

A bit off topic, but do you know if anyone has had much success re-valving the sff forks on the 2011+ kx250f, not for MX though?

[Crabby]

Have you looked at motoxparts.co.nz for the crank ?


Good thing you went for the 07 being a 'plus size' rider.

:laugh::laugh: for the gearbox? I was talking with Brian at Mr Motorcycles and he rcommended I get an 07 and then one came up that had just had some lovin there so I bought the sucker! Can't say enough good things about these guys!

This pic gives you an idea of just how plus sized I am lol... Currently carrying about 30kg's of extra ballast. :laugh::laugh:
http://iforce.co.nz/i/k3yeag0g.rie.png

[scott411]

A bit off topic, but do you know if anyone has had much success re-valving the sff forks on the 2011+ kx250f, not for MX though?
I would have thought most of the bigger guys, (norm cobb, jimmy at performance factory, richie at moto sr, mark patterson would have all had some expericence with them now, Jason DIckey who won the nz cc champs juniors last year ran std suspension as far as i know

[motor_mayhem]

And I thought I had it bad

http://www.trademe.co.nz/a.aspx?id=449205550

[thecharmed01]

So what's the verdict? You gonna pick up a piston kit?