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Sheep Dags
9th March 2004, 10:35
Hey guys,

I've just gone out and done something silly... I bought a TZR250, well because it fuckin kicked ass!... which seemed sweet when I bought it but gradually wouldn't start so easily, now hardly starts at all, unless I push it for miles and miles. I changed the plugs and even the battery cause it was flat but that didn't help. Was telling a guy at the garage exactly what I just said and he reckons it's a problem with compression, cause yea, when I kick it, it doesn't feel as though anything is happening. Anyway so he reckons it's siezed!! - I don't know exactly what happens when a 2 stroke siezes but i know it's BAD and COSTLY. Does anyone know of any 2 stroke whizzes out there who wouldn't mind having a look for me to see what's up, and to see whether I've bought a lemon or not :( Cheers heaps
- Mike

P.S. I'm out at Torbay in Auckland but can transport it in my van if need be :D

White trash
9th March 2004, 10:39
Hey guys,

I've just gone out and done something silly... I bought a TZR250, well because it fuckin kicked ass!... which seemed sweet when I bought it but gradually wouldn't start so easily, now hardly starts at all, unless I push it for miles and miles. I changed the plugs and even the battery cause it was flat but that didn't help. Was telling a guy at the garage exactly what I just said and he reckons it's a problem with compression, cause yea, when I kick it, it doesn't feel as though anything is happening. Anyway so he reckons it's siezed!! - I don't know exactly what happens when a 2 stroke siezes but i know it's BAD and COSTLY. Does anyone know of any 2 stroke whizzes out there who wouldn't mind having a look for me to see what's up, and to see whether I've bought a lemon or not :( Cheers heaps
- Mike

P.S. I'm out at Torbay in Auckland but can transport it in my van if need be :D

You poor bastard!

Yamaha 2 stroke parts cost a fortune. Tow it to a bike shop or any work shop for that matter and get them to perform a simple compression test.

Wont cost much but the repairs probably will. I'd be happy to help with repairs but it's a bit far to commute.

Sheep Dags
9th March 2004, 16:28
thanks for the reply,

Does a lack of compression definately mean it's seized or could it just mean there's somthing else wrong with the engine? i.e. something not so expensive :D

- plus, if I actually DO get it started very occasionally doesn't that mean it's not siezed? seeing as I can take it for a ride etc etc, just when i next try to start it up it won't go again :(

Two Smoker
9th March 2004, 16:36
thanks for the reply,

Does a lack of compression definately mean it's seized or could it just mean there's somthing else wrong with the engine? i.e. something not so expensive :D

- plus, if I actually DO get it started very occasionally doesn't that mean it's not siezed? seeing as I can take it for a ride etc etc, just when i next try to start it up it won't go again :(
Lack of compression could mean that your rings are gone, still costly though:confused2 . If you want to save $$$, get a manual take it apart and see what the problem is, as long as its something like a Haynes manual you can't go wrong

FzerozeroT
9th March 2004, 17:33
if it's seized you wouldn't be able to kick it over, if you have any mechanical nounce (and a torque wrench handy) pull the head off, just the top not the barrell, inspect the cylinder walls, top of the piston, and combustion chamber (take photo's if you can) then tell us whats happening.

edit:

use the torque wrench to take it apart, if the nuts are unevenly tightened then the guy before youcould have swapped the rings from one cylinder to the other or something else dastardly, someone that low wouldn't bother to use the proper tools either (SCUM) look for anysigns of a cheap fix-to-sell job

curious george
9th March 2004, 17:40
Give me a ring. I'm in Devonport, so can ride up after work or summit.
Pm'ed :msn-wink:

Andrew
9th March 2004, 18:23
Speak to Dave. Dave all the way!

Wellyman
9th March 2004, 18:56
Hey sheep dags I got half maybe a full TZR 250 motor and live in Auckland give me a PM if you need parts because I might have them!

speedpro
9th March 2004, 18:59
If someone has been messing with it prior to sale they could have reused the piston circlips and they could have come out. You also haven't mentioned the injection oil, either because it's too obvious or you don't know to check it. They're good bikes but must be put together properly. I have all the tools so if you get stuck let me know, plus Henderson Yamaha is just down the road - for bits.

Sheep Dags
9th March 2004, 19:53
Thanks heaps guys,

I've got a receipt here from Mt Eden motorcycles from when he took it in to get the rings replaced so they have done that but maybe they fucked it up when they put it back together or something I dunno, and I'm sure if there were big problems with it they would have noted it.

George I'll give you a call tomorrow but won't be able to meet with you cause I'm busy after work but would definately be keen Thursday.

and I'll definately consider the offers of parts etc etc :D
thanks heaps I'll let you know what happens.

pete376403
9th March 2004, 22:36
A full-on siezure will lock up the motor and it will stay locked, even after its cooled down. Your motors lack of compression indicates its had a partial siezure and piston ally has been smeared up over the rings, wedging them in the bottom of the grooves. New piston and ring pack time, plus rebore. If your motor uses chrome plated bores it's prolly going to cost you big time (Desperate - ie Friday night before a ride and no spare rings in the country - people have been known to extract rings from pistons and reuse them).

Usually caused by running too lean / air leak in the inlet manifold, etc. Running out of oil (in a bike which uses a seperate oil tank and pump system), the crank is more likely to fail before the pistons.

Adding more oil (beyond the correct ratio) in a premix bike will not help - if anything it will make matters worse - if the motor is running lean and you increase the amount of oil going through the carb jets then at the same time you must be reducing the amount ot fuel going through ie even leaner than before.

MrMelon
10th March 2004, 07:32
He didn't say there's a lack of compression.. every now and then it'll start and be running like it should, but it's just impossible to start, so it shouldn't be seized at all?

Sheep Dags
10th March 2004, 13:49
yea definately gotta be a lack of compression but what I don't understand is that once I finally get the fucker started, it goes sweet, i mean i can take it for a thrash and it's all good. just getting it started is a real cunt!

Two Smoker
10th March 2004, 15:03
yea definately gotta be a lack of compression but what I don't understand is that once I finally get the fucker started, it goes sweet, i mean i can take it for a thrash and it's all good. just getting it started is a real cunt!
Maybe your pre ignition has gone kaput, get that checked out.

pete376403
10th March 2004, 22:27
Maybe your pre ignition has gone kaput, get that checked out.

What do you mean by "pre-ignition". That phrase is usually used to define uncontrolled ignition, aka 'pinging' or 'pinking', and in the worst case, 'detonation'. Expect to find the piston crowns all over the crank shortly after that starts.

Dave
11th March 2004, 08:20
Hi Daggs,
Bring it down to my workshop, I'm at 60 Hillside rd in glenfield.
I'll have a look and give you some good FREE advice. and then if it needs something done maybe we can work out a deal or something.
I am a qualified auto mechanic and have been racing 2 strokes for nearly four years. I have always done all my own engines and in all that time racing, I have never had one sieze. Also done a lot of 2 strokes for other people.
leave it to you.

Cheers, Dave

Sheep Dags
12th March 2004, 08:01
Sweet thanks heaps Dave,

I'll bring it in today. I have the day off.
cheers,
Mike

Sheep Dags
14th March 2004, 20:23
OK,
Turns out it was a matter of a flat battery and fouled plugs. Thanks heaps Dave, you're a legend!
and thanks everyone else for the advice.

- Mike

Rocket
15th March 2004, 08:42
what a great community! Nice work. heh that sure saved you some bucks eh :P