Minibike question.

[Aero165]

Are these bikes the same?

http://www.trademe.co.nz/Browse/List...x?id=126663801

And

http://www.trademe.co.nz/Trade-Me-Mo...htm?key=259929

The repsol one appears to have twin front disks. Are these what you call a B1 rep bike?

[dirtybomb]

Gidday, your looking at what I have along with two friends.

Excelent value for money, keeping in mind you get what you pay for.

They are probably made by 8yo girls in China (not far from truth), with the mechanical aptitude of a toasted sandwich.

So; Loctite 609 on all critical bolts/nuts/screws
Tighten up throttle mount on handle bar, I ended up using CA to keep it still.

Check adjustment of front/rear brakes.. My ones were not straight and creating drag on brake disk when not applied.

Adjust Chain, a loose chain will hinder power ALOT. Remember youve only got about 2kw to play with. Dont over tighten, and I sugest a sticky chain oil which is available ex Saeco bearings etc

Also, the foot pegs are shite BUT dont buy the aluminum ones off trademe cuz they are not ok to race with (damages track). I made my own footpegs.

A good idea is to buy an aluminum pullstart too.

Be nice to clutch if you are close to 80kg.

Thats just to start with, but dont be afraid to pull shit apart.. They are simple as. CHEAP for parts. (way simpler and cheaper to run than my rc cars!)

Hope this helps!

[Aero165]

That sure did help! Thanks!

[Aero165]

http://www.trademe.co.nz/Trade-Me-Mo...htm?key=224571

Is it worth going to a water cooled version? How often should I expect to do piston and rings on a model like this?

[Gadgit]

Hi there Aero
The B1 rep shouldn't need a piston replacement for a long time there are guys in the New Zealand MiniMoto club that haven't changed there piston for 2 or 3 years even so a piston is only $10 and a ring $8..... one thing I would do is strip the engine and fit a replacment small end bearing (not a china made one) $15.... a few of these 6.8hp engines have been knowen to throw this after a 20-30mins of running time if this happends you will need a new piston and ring.
You wont be able to change the foot pegs on the one you are looking at tho because they are part of the frame.

Hope thats helpful to ya

[Aero165]

Hi there Aero
The B1 rep shouldn't need a piston replacement for a long time there are guys in the New Zealand MiniMoto club that haven't changed there piston for 2 or 3 years even so a piston is only $10 and a ring $8..... one thing I would do is strip the engine and fit a replacment small end bearing (not a china made one) $15.... a few of these 6.8hp engines have been knowen to throw this after a 20-30mins of running time if this happends you will need a new piston and ring.
You wont be able to change the foot pegs on the one you are looking at tho because they are part of the frame.

Hope thats helpful to ya

Wow, thats a while. I'm used to riding 2T MXers. My YZ was like $500 for a full top end rebuild. So $18 bucks is cheap as chips!

If I tear the motor down to replace those bearings will I need to replace the gaskets?

I have a mate that works with sheet metal and he can wield all kinds of metals so that the foot pegs shouldnt be a problem.

Without trying to be to rude, could someone have a geeze around trademe and point me in the right direction? There are some bikes on there that look exactly the same but some have twin disks up front and others don't, and I've heard some models of similar looking bikes and the same price range are of better quality.

Thanks!

Aaron

[Gadgit]

Most of the time when you pull the barrel off the water cooled engine the gasket will stay in one piece so it's just a 5 min job... barrel off gudgon pin out fit new bearing refit gudgon and barrel done... if you remove the head tho then you will have to replace the 2 o-rings which are readly avalible at bearing outlets ie Seko bearings.. To race all you will need to do to the foot pegs is get some round nylon cut to lenght and drill a hole to replace the flimsy rubber foot pegs that they come with no welding required.

[Aero165]

Thanks Gadgit!