my bike is a heap of junk

[neeeel]

My bike ( tzr 125 ) is really starting to piss me off now. I replaced the water pump seal a few weeks ago, and it seemed to be ok, the gearbox oil was normal , until today when i looked, and its gone mayonnaise again. I think i put the seal in ok, so where could the water be coming from? Someone has mentioned that the head gasket going could let water into the crankcase, but someone else has told me that it couldnt get into the clutch cover ( the right hand side as you sit on the bike). maybe its getting into the crank case, and my crank seals are gone?
I am on the verge of giving up and selling my bike. Apart from this, i still have low power and performance issues, and dont know where to start.

[Whosthedaddy]

Dude that sucks.

You've got to weigh up the pros and cons of keeping the bike.

My pile of poo is a rusty turd, I've had a go at keeping it on the road, I've learnt from it and tried hard not to spend too much on a bike that is'nt worth it.
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Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[mr jamez]

What method did you use to install the seal? sounds like it is not installed correctly or has been damaged, no other way for water to enter the gearbox.

If your bike is performing badly then you need to service it and check the compression.
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NSR 125F > BROS 400 > NC30 > BROS 400 > Trumpet S4 > '97 VFR 750

[Paddy Blake]

The shaft that the seal goes on may have been damaged or worn.
You could go to the brakers and buy a caseing with the pump on
it and switch the casings.Then have a look at the shaft and seal
on your old one to see what the problim is.

[neeeel]

ive done a few things to it, cleaned the carb, checked the air filter, tried to clean out the exhaust. I asked the local yamaha dealer about a compression test, and they said they could do one, but it wouldnt really locate the problem, other than it could be cylinder, or it could be crank seals, they said it may cost hundreds of pounds of work to get it working properly and that is more than my bike is worth really, so i dunno what to do
what if i bought a new( second hand) cylinder, and piston, changed the crank seals, and fitted the new cylinder, would this help any?
should i just go for the rebore anyway, was quoted about £90 for this.

[mr jamez]

A compression test WILL be useful, as it will give you an idea of what sort of condition the engine is in. You don't want to spend lots of money on tearing the engine to pieces when you should be looking at the carb or another component.
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NSR 125F > BROS 400 > NC30 > BROS 400 > Trumpet S4 > '97 VFR 750

[stevo as b4]

You could chance it with a spare engine from a broken TZR. This is likely to be cheaper to source, than a full engine re-build with all brand new parts as needed. The only problem with secondhand 2 strokes, is that you will have no idea of how much life there is left in a spare engine, or if it too is knackered, until you install it and get it running. Im sure a working TZR engine could be found either from a breaker, a cheap crashed/damaged stolen&recovered bike, or maybe someone has a spare engine for sale on Ebay?

Unless the rest of the bike has alot of worn parts or needs much money spending on it, then don't give up on it mate! An engine really isnt the end of the road like a bent or broken frame etc!

[Gradog]

If your suffering loss of power, and water in the oil, it is most likely that you have a weep on the cylinder head gasket. It does not have to be large, and you probably won't be able to see it until you have taken the cylinder off.
Don't go buying new engines or F**k about when the chanes are that will only cost a few quid and a couple of hours to prove it.
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Grey haired bikers don't get that way from pure luck. Only a biker knows why a dog sticks his head out of the car window.

[neeeel]

so how do i know if the head gasket is weeping?

[Gradog]

A compression test may tell, if it is bad enough. Chances are your exhaust will turn whiter, as she runs on tick over. Effectively what happens is that the piston draws in water on the compression stroke.
It then pushes it out on the firing stroke, giving a poorer burn, and pushing pressure back into the engine crank cases. A small amount of water is then pushed into the oil. Treat it early and no damage will be done. If your looking at the gasket after head removal you will see a track mark, to one of the small openings that goes throgh the cylinder head carrying water around it to keep it cool.
Oh and you can also help prove it by removing the cap off your radiatior, Normally it will not matter if you run low revs. If it has gone you will find water pushing its wa out bercause of the increased pressure.
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Grey haired bikers don't get that way from pure luck. Only a biker knows why a dog sticks his head out of the car window.

[Gazdaman]

Also you can buy compression testers off eBay for under £20.

Gaz

[neeeel]

it does seem to be only a small amount of water at the moment, since my oil window, and oil seem clear now, so is that kinda pointing towards water being forced through the crank seal?

[finpos]

Firstly, don't panic.

If the gearbox oil has been previously contaminated with water, it may take a couple of oil changes before you get rid of all the mayo. The important thing to look just now is if you are actually loosing water from the water tank.

Secondly, panic.

You may have made an arse of it. But if it's been working ok for a while, that's probably not the case.

But you do need to worry about the crank seal, and, more to the point, why did the original one fail in the same place. Could it be the reason the new one has failed also? This could be down to either a scored/damaged mating surface, or the bearing behind it being worn as well.

Hope it's the "don't panic" option

finpos.

[neeeel]

it wasnt the crank seal i replaced, but the water pump seal.
Its hard to tell if i am losing water or not, the radiator doesnt seem to be full, but that could just be because all the tubes are full up, and the overflow bottle is full atm, so i dunno

[finpos]

Ah sorry, my mistake, Same applies to the water pump shaft/bearing

You need to get to the bottom of this water thing before you worry - fill up the radiator through it's cap, take some water out of the tank (it should only be half full), mark the level it's at on the tank with a pen, ride round on it a few days. Only check the water level when cold - it'll go up and down a bit with water temp.

you might seem to "loose" a bit of water at first, but don't worry about that - you are looking for the level to stabilise over a couple of days.


finpos.

[neeeel]

just noticed a big F**koff hole in the bottom of my engine. Could this be the cause of my loss of power and performance, since i heard that the crankcase is under compression too during the piston stroke. The hole is about the size of a 2 pence piece

[Gazdaman]

Depends what's coming out of that hole. If it was a problem I'd expect either petr-oil to be coming out, or water.

If it's neither, I'd say it's not a huge problem other than letting in dirt/crap.

Where is the hole and what's behind it?

Gaz