SERIOUS 155z Issues.

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Mine has the upgraded bearings but just the 5 plate clutch, i assume there will be stuff all difference in the manuals/engines but hey Ive got one saved on my computer if anyone needs it.
 
hey peter i was just reading an old thread and came across this
i love my 155z.. simply wouldnt buy a daytona.. sure if i was sponsered i would ride one.. but my choice.. i would stay with the 155z..

MV24- you must be hearing things because pretty much the whole race team Ken from DHZ has are running 155z's so they arnt shit.
oh and please please dont go to fx racing. or wherever the hell u go because EVERYTIME they rip you off. They will get you everytime. they can probably sense your presence haha and then bump up all the prices. shop around, learn a bit, and do it YOURSELF, oh and teach you dad a thing or two because if he cant put in an engine..... might as well give up now.
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LOL just the first bit not the rest hahah What happened? do you still think this now hahaha
 
Its a chinese engine , you cant expect them to have no problems forever

And if it was a fault at the start , bent shift forks? then even then 6 months is a pretty good run lol
 
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'Nothing really related to this thread but it does show that even expensive Jap bikes can have tranny problems :

Here's a link showing what shift forks are ...

Dan's Motorcycle

There's some info on jumping out of gear in this link ...

Motorcycle Repair: second gear, yamaha r6, drum groove

And a shift star came loose on this guys bike ... the 4th pic down shows shift forks ...

transmission stuck in gear - couldn't shift...fixed : Suzuki GSX-R Motorcycle Forums: Gixxer.com

BMW's have "roughly made" trannies which have all sorts of weird problems ... Reading up on things like that can give you ideas which can be applied to help you in diagnosing problems/symptoms encountered with other trannies ... I have ALWAYS "bench tested" my trannies to ensure they're shifting correctly BEFORE closing the cases up ... It's too late to discover a problem after the engine is back in the bike ... LOL ... I learned that extremely quickly ...

IF you do everything right you'll know 100% BEFORE closing the cases that the tranny will shift smoothly and positively ... What you do is shift thru the gears and check that the mainshaft gears are lined up spot on with the countershaft gears ... and that the shift forks aren't rubbing on the sides of the dog rings ... There's some info on bench testing down the page in this link ...

BMW motorcycle transmission, tranny, gearbox, repair, maintenance, driveshaft bolts, hypoid, synthetic, oil, lubrication, clunk, shift lever, jumps out of third gear, kick start lever
 
If you read what that guy was saying about the cast dogs not being equi spaced in comparison to the slots/holes on the driven gear ... You'll realise as he is saying that only the dogs that touch the sides of the holes are taking ALL of the load and impact ... and being a cast gear ... the dogs can be easily broken off ... IF the same situation exists in Chinese trannies (I haven't checked) ... then that could explain why there's a lot of failures ...

A smart fitter would check to ensure that the sides/ends of ALL of the dogs touch the sides of the holes at the same time and IF not ... they'd carefully die grind the ends of the dogs until all of them ARE touching at the same time ... That way they'd all share the load and wear ...

Also note in one link where they state that bikes left in gear on trailers get their trannies pounded when they move back and forth or up and down ... The dogs will smack into one end of the slots ... then smack into the other end repeatedly ... Not too many people would even imagine that transmissions could get damaged that way ... Personally ... I don't like elongated slots in gears ... they're ridiculous from an engineering point of view for the reasons explained in that link ... Hard downshifting also pounds the crap out of the dogs ...
 
yep a few of my jap bikes in the past have sht the gear forks... 86 yz250, 90 yz 250, 92 yz 250 and my current 2005 wr450(shat 5th)
 
09crf_149 said:
hey peter i was just reading an old thread and came across this
LOL just the first bit not the rest hahah What happened? do you still think this now hahaha
Click to expand...

dont rub it in lol.

Nah they are sik engines.. myn has just thrown in the white flag.
 
ok guys.. got the clutch off and the gear shifter shaft and all the "outside" gearing components and they all seem fine..

any stabs as to what to do next??
 
so the gear shift shaft slide out easy?

maybe time to split the engine open man... most the time with gear problems other than a gear shift shaft you cant easily see them..

have you spoke to ken about this issue yet... he deals with it every day so he'll more than likely be able to tell you what to replace..
 
yeh its slid out easy as.

ken reckons maybe the shifter drum.. but he said he couldnt really tell. i think is time to split the cases to.. so the head and everything comes off completely.. do i need to remove the other side of the motor?
 
throw it out and buy another $265 "glee" club engine. remember time is money.
 
no way im chucking it.. im not made of money. i respect my stuff.

i have split the cases everything looks absolutely fine.
but!

the shifter drum and selector forks where stiff and machined poorly.. Pitbikekid will upload some a video of it tonight.


What are your thoughts? i reckon it has been a factory lemon.
 
Ill chuck my bottom end at you if i decide to bin mine

Mite be a while saving pennies for a new bigger motor
 
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