[christddel]

The quality of bearings...

On the crankshaft is the C3

But my question ?

for the gearbox C2, C3, C4 ?

After disassembly, I have only these references...

xx-xx-xx The measurements are in millimeters

 

[qwerty]

Take the bearings to a bearing supply house to match up, but do not be surprised if they are proprietary sizes and only available from Yamaha.

 

[christddel]

Take the bearings to a bearing supply house to match up, but do not be surprised if they are proprietary sizes and only available from Yamaha.

Thank you for your reply.

I have found a supplier for these bearings.

But, I was offered the same bearing in different quality finish. C2, C3, C4...



What is the best for (axis) gearbox ?

 

[uktw125]

The codes c2,c3,c4 are different internal clearance specs. to allow for different rates of expansion of the inner and outer race.

If there is no c# number then they are standard clearance.

A bearing with more clearance than standard is safer to use if you do not know which is correct, so I would use c3 (more than standard clearance than standard) if I could not find out the full and exact spec.

 

[christddel]

The codes c2,c3,c4 are different internal clearance specs. to allow for different rates of expansion of the inner and outer race.

If there is no c# number then they are standard clearance.

A bearing with more clearance than standard is safer to use if you do not know which is correct, so I would use c3 (more than standard clearance than standard) if I could not find out the full and exact spec.

Thank you for the information technology.

I'm reassured ...

My bearings are ordered.

 

[christddel]

I received the bearing...

Now the reassembly of the engine...



Changing the crankshaft Modified stroke 48.8 mm ---> 62 mm. (Work TW-parts)

Changing the piston 57 ---> 73mm.

Cylinder/Sleeve 225.

Calculate this is ...259cc only...



Changing gearbox TW125 5 speed for TTR 225 6 speed.

 

[qwerty]

259,598428571428571428571..., actually. You are building a TW260. Try to keep it down to 160kph.

 

[uktw125]

Great build, please keep us up to date as you progress.

 

[christddel]

reat build, please keep us up to date as you progress.

Following the mounting of the cylinder 73mm.

I must know the volume of the combustion chamber

With 30 cc combustion chamber volume, I put a head gasket + fin ...

 

[RobRz]

Hi christddel, did you replace the left side crank bearing? if so how did you get the cam chain sprocket and old bearing off?



cheers

Rob