TOPIC:

Hi propforward,

How is it that you broke the nylon gear while removing the block? I know that this has been a common problem for owners doing overhauls. I looked through the FAQ but couldn't find it there.





If we could come up with a method of avoiding this problem I'll add it to the FAQ.

Thanks in Advance.

Bill

Great info guys, thanks.

I will definitely put the cylinders and head on a surface plate and check them carefully, and checking the bores and bearings makes sense at this point, since I'm in there.

Regarding stem seals - I have some stem seals already, that were in the aftermarket gasket set that came with the bike. Any reason not to use those? Obviously not as good as the blue ones mentioned, but they should do the job? If they are known to be weak then I'll get new ones. It does make sense to check out the valves and seats and stems etc being as I am this far into it.

I don't think I will put a LOT of miles on this particular bike. I do the high miles on my other bikes, so I don't know that I need the really good seals being as I already have these others.

KZQ wrote: Hi propforward,

How is it that you broke the nylon gear while removing the block? I know that this has been a common problem for owners doing overhauls. I looked through the FAQ but couldn't find it there.

If we could come up with a method of avoiding this problem I'll add it to the FAQ.

Thanks in Advance.

Bill

Good question Bill, and it is embarrassing as hell really.

As far as I can tell, the previous previous owner had the block all apart, and all the bolts on that cross shaft were tighter than hell. I simply could not get the bolt on right side of the shaft out to remove it. Now - I only wanted to remove the shaft so that I could get at the nut holding the water pump impeller shaft off, which had been rounded off by previous previous owner, so I needed the clearance.

Anyway, I resorted to an impact wrench, but the flats on the shaft rounded off, and spun the assembly. Since it wasn't all lined up right it bound the gears and broke a couple of teeth. I'm pretty sure I broke it.

In the end, I had to get a monster pair of vice grips on the cross shaft, and finally busted the bolt loose with the impact wrench.

Having done all this, and royally farked the thing up,I think in future if I have to do this again, I might just take the barrels right off, and deal with removing these shafts on the bench, because you can turn them upside down and get better access.

Otherwise you have to make sure that plastic gear is pushed right into its hole. And you absolutely must not let the assembly slip or bind.

When I put it back together I'll have another look at the assembly and procedure, and think it through.

OK,

Its obvious by the pic above this nylon gear on your bike is no good now due to damage, but if you look at it closely there is virtually no WEAR & TEAR at all. Plenty life in it left.
DID YOU MANAGE TO RETRIEVE THE BITS OF NYLON GEARS FROM YOUR ENGINE ????

What this proves is that they are good for many miles before needing replacement despite being made from nylon.

As mentioned earlier, the only time I have ever had to replace one was due to damage or the engine running too hot (low on oil or coolant) which makes the nylon gear soft & break free from the centre shaft.

Many people worry about this nylon gear failing, but there is no need as long as you keep your oil & coolant levels good.

Regards

Pete F

strate6 wrote: OK,

Its obvious by the pic above this nylon gear on your bike is no good now due to damage, but if you look at it closely there is virtually no WEAR & TEAR at all. Plenty life in it left.
DID YOU MANAGE TO RETRIEVE THE BITS OF NYLON GEARS FROM YOUR ENGINE ????

What this proves is that they are good for many miles before needing replacement despite being made from nylon.

As mentioned earlier, the only time I have ever had to replace one was due to damage or the engine running too hot (low on oil or coolant) which makes the nylon gear soft & break free from the centre shaft.

Many people worry about this nylon gear failing, but there is no need as long as you keep your oil & coolant levels good.

Regards

Pete F

Good points, and I completely agree. The gear is definitely up to the job. I have no concerns at all about putting a used one in good condition in there.

I did retrieve all the broken bits. I have them in a bag with me right here.

Great job mate !

I am in the final stages of rebuilding my own top end after a full overhaul (valves, seals, rings, honing, water pump seals etc, etc...... so if there is anything I can help you with just ask.

I have no doubt at all you are fully capable of doing the job yourself, but its all fresh in my mind & have built more than I can remember !!

Regards

Pete F
UK