Grubee skyhawk 2 gearbox question

[Irish John]

use 5oz no more of oil !!!!!

Can someone tell us non-imperial measure guys how much is 5oz?

 

[azbill]

40ml per liter gives you 25:1 (same as 5oz/gal)
here is a good ratio calculator
http://www.csgnetwork.com/oilfuelcalc.html

 

[HoughMade]

This is not for mixing.

That would be a hair under 150 ml.

 

[azbill]

oops
I guess I kinda jumped the gun

 

[nsideus]

I try to locate the gearbox hole where the clutch bell housing holes are this gives it and opportunity to reach the clutch plates. With the gearbox engaged rolling the bike backwards rotates the bell housing. Oil the clutch plates and inside the bell housing before assembly. My first gearbox I used grease and had to take it apart because it kept sticking and I greased the clutch well. I am not saying this is the way to do it it just has worked for me. I have been using high temp rtv silicone gasket maker on another gearbox I have not had to take it apart but I would probably need to replace the silicone if I do.

 

[Irish John]

How much does it leak if you don't use silicone gasket sealant? I just don't want all the hassles of an HT with a 4-stroke. Incidentally if you factor in the amount of engine the 4-stroke is probably cheaper than the HT. It is certainly better value.

 

[HoughMade]

I don't know how much it would leak without silicone, but that is why I would put in a drain hole and a hole to check the level as well. That way, you would not have to take the cover off to drain.

 

[Irish John]

Thanks HoughMade but how do you make the drain hole leakproof? Also to what depth in the gearbox do you fill the oil up to? Half way up the gear wheels? There'd need to be a good depth for the oil to get splashed around to all the cogs.
Does the centrifugal clutch really need lubrication?
Lastly, how do you drain the oil from the engine without turning the bike upside down?

 

[HoughMade]

How far do you fill it up? I don't know- I have run mine dry so far. However, on general priciple, I would think it needs only have the largest gear dip into the oil- the oil will climb to the rest of the gears....provided conventional oil is used...and I would not see a reason to use anything else. Synthetic gear oil does not climb as well which is not a concern in a pressurized oil system, but is a concern when lubrication requires the oil to cling and climb. I personally do not see a need to bathe the clutch, but I would like oil on the gears. Others want the clutch to run in the oil....so far, I do not think there is any consensus.

As for making the drain hole leak proof- the same way a drain plug on a car does not leak- drill the hole, thread it, and plug it with a bolt, washer and rubber washer.

 

[Irish John]

Thankyou so much HoughMade. I reckon I'll try it with my gears greased for a short while to see and then I'll do the oil bath idea. I'll keep the clutch dry to see hopw that goes. Any problems and I'll go for the oil.
How are we expected to drain the engine oil (not the gearbox oil) from the motor sump? It has to be done rather too frequently and I suspect the every 10 hours is a bit of a ridiculous statement from the manufacturers. Every 10 hours is every 250km and that is about once every 8 days for me which makes things very labour intensive. Especially if I have to take the motor off to drain it,