GP100/125 engines for sale?

[MarlinHemi]

anyone got a running gp100/125 engine for sale mines ticking a bit im just gonna ride it till it blows then chuck a new engine in ive seen them go pretty cheap!

[Grumph]

All the GP100/125 engines I've been offered in the last few years have been kitsets.
I suspect a complete runner is pretty rare now....

[MarlinHemi]

There was a gp125 motor in chch for 100 bucks exactly when i had no money, sigh

[MarlinHemi]

Do tf125 motors fit in the same mounts

[TZ350]

There was a gp125 motor in chch for 100 bucks exactly when i had no money, sigh
All the GP100/125 engines I've been offered in the last few years have been kitsets. I suspect a complete runner is pretty rare now....

The recent CHCH one had the cylinder and head off. I understand the buyer brought it for parts.


Do tf125 motors fit in the same mounts

No

[Askor]

mines ticking a bit

Take it apart and find out why


im just gonna ride it till it blows

Don't do that

This could be a great opportunity for you to figure out how an engine works, and hopefully get some experience fixing them. You can't break something that's broken..

[MarlinHemi]

Yeah just gonna see what happens im gonna get a gasket kit take the head off see how piston is hopefully its just that but if its the crankshaft or even worse ill just put it back together and perhaps swap one of those loncin ax100 engines in, Another question do you just need vernier Calipers or get it professionly measured for new piston size? thanks for all the help!

[husaberg]

Another question do you just need vernier Calipers or get it professionly measured for new piston size? thanks for all the help!

No on verniers.

if the engine was sitting for an extended period prior to you its likely the big end was rust damaged.
It would still be cheaper/better to rebuild the crank and do arebore, than to repower the bike.

[MarlinHemi]

it has not been sitting hopefully just needs a piston will be taking ir apart tonight and will post some pics

[MarlinHemi]

So i took it apart cylinder looks good to me anyway piston seems okay but there is a bit of play when you twist the piston (gently) http://s1268.photobucket.com/user/Marlin_Robertson/library/?sort=3&page=1

still makes that ticking noise (YES I SEE THE HAIR ON THE PISTON I GOT RID OF IT LOL)

[Grumph]

So i took it apart cylinder looks good to me anyway piston seems okay but there is a bit of play when you twist the piston (gently) http://s1268.photobucket.com/user/Marlin_Robertson/library/?sort=3&page=1

still makes that ticking noise (YES I SEE THE HAIR ON THE PISTON I GOT RID OF IT LOL)

i bloody hate photobucket. It takes so long to come up for me that i've now got more time invested in you than i wanted...
If you can twist the piston even slightly there's wear somewhere.
I'm going to go out on a limb without seeing it but it's probably a worn gudgeon pin. I've seen the wreckage of several of these and if it's been rebored with an aftermarket piston and pin, it's likely to be worn where the roller bearing small end runs. The cheap aftermarket pins are notoriously soft.
A worn pin would give you your ticking noise.

The barrel and piston will have to come off to confirm this. If you're careful you should be able to save the base gasket. Piston circlips are cheap.

If this is as i expect, the piston is probably still good so you would need a genuine piston pin and needle roller bearing.

[MarlinHemi]

sorry about photobucket... so I will have a look sometime and see how it looks, Thanks a ton!

[MarlinHemi]

Its all apart we bit beyond me, anyone in chch that could do a cheap top end rebuild?

[Askor]

Pictures are always nice, specifically ones of the piston thrust faces, and the wrist pin. Good lighting and focus is key. As Grumph says if you're lucky you'll just need a new OEM wrist pin & small end bearing. Feel free to send me a PM if you want.