Hi all,
In the HRC manual is says to swap the transmission for the NC30 set. It says in the manual that i should use the counter shaft from the RVF. What do they mean by "The counter shaft"

Cheers

The bike has an input gearbox shaft which is attached to the back of the clutch assembley and an output gearbox shaft which ends in the sprocket mount outside the engine.

The output shaft from the gearbox can be called a countershaft, layshaft, output shaft etc.

Some vehicles use more than two shafts so you could have an input shaft, layshaft and an output shaft. They tend to be interchangeable terms when there is only two but probably only for non-mechanics.

This is a good example of "If you have to ask" then don't do it!


HRC manual also says file your inlet rubbers to flush with the carbs, port the heads, run wider valve clearances etc etc

Are you building a race bike?

I agree with the "If you have to ask" but if i dont ask i will never know. And i live so far from civilisation that i have to and like to do the work myself.
Yes i am building a race bike and this has been a bit of a troublesome effort, i threw a valve in my RVF engine so have put an nc30 engine in for the time being, but am having trouble getting the carbs sorted.
The idea with the nc30 engine was to use it for parts i.e valves and the gearbox; but use it in the mean time while i get the RVF cylinders re-sleeved.
I have the nc35 engine in bits at the moment and thought about swapping the transmission over while i have it apart.
Now i know what the counter/output shaft means my next question is, do you swap out the complete unit pinions and everything or just the actual shaft and bearing?
Cheers

I presume you would use the complete shaft as the reason for swapping it is probably to change the gear ratios.

Your getting the damaged bores re-coated with nikosil and honed to spec ? About £400 for that work isn't it ?

If you mangled a valve i presume your replacing the piston, piston rings, valve springs and valve guide bush too ?

I hear you. I would fit the RVF heads and cams to the 30 motor and go from there.

Have a read of G Force's blog - mngforce.typepad (or something like)

The engines are the same apart from heads and so seeing as you have the 30 running then you are good to go!

Yes i may well do that CMSMJ1, save myself some cash
I agree Old painless i would think that you change everything, my translated copy of the HRC manual isn't very clear.
I was planning on getting the 1 and 3 cylinders re-sleeved as they are too badly damaged. i have 2 new pistons and rings and plan to use the existing un damaged ones. i also have a second hand crank as i want to get the other cheked as it may be damaged.
I have a second hand head to replace the damaged one and have checked the springs and lapped the valves in, so it should be good to go.
This is the no 3 piston that got damaged,


Hope this works this time, tried to post this pic but wouldn't work

Is that a big hole in the piston crown ? Eeek !

You may need to replace all your bearing shells and main bearings if that much debris has been floating around the bottom end. It would probably be a good idea to take the whole thing in pieces to a local engineer and get the whole lot thrown in a parts washer really. If any debris gets left in the bottom end and gets taken up to the piston skirt by the oil pump it could destroy the new coating and seize again.

Just out of interest, is the cross-hatching from the OEM honing still present on your good bores and whats the mileage on the engine ?

Yes sure is, the head looks like it is made out of plastercine and been used as a hammer too.
I have a new crank and shells, and i will get it all cleaned properly just a matter of getting all the cash needed. I might well take CMSMJ1 advice and just swap the heads over. Much cheaper and it would kind of sort out the transmission too.

The cross hatching is pretty much gone on the good ones, so will have them honed too. the engine had done 38k kms.

I think i was quite lucky in that the valve heads snapped off and got jammed in the head, one did make it through to the bottom end, but i have found most of the lost parts. Some went through the exhaust some into the carbs and some into the sump.
The engine went pop at Pembrey going through woodlands, lost all power so i pulled the clutch in and coasted into the pits. I guess i am quite lucky as it could have been much worse.

You must have been weeping when you got it open mate. Sorry for your loss.

From the two NC24 engines i have had open and what you have said about the mileage on your engine it seems the cylinder walls wears awful quick on these bikes.

Why is that ? Thin nikosil or low oil flow ?