RegionX wrote:Some more things I'm wondering about....

1. Assuming I can get to all the problem areas, is it safe to weld the exhaust pipes while still on the bike?

2. What grade stainless are they made from? I need to know what to buy to weld the holes up.

3. What are the chances cleaning the clutch plates will make a difference, I'm selling the bike so not too keen to invest in new plates?

4. I have aftermarket fairings that don't allow for the original coolant overflow container, the previous owner has cable tied a 500ml bottle to the top rad and hooked it up. Not only do I not know how much to fill it but I'm also unsure if the position of the bottle is going to affect the cooling system.

Hope its not too many questions...

I take it you mean the collars where they join have rusted? This part is mild steel.. you can chop them off and weld somethign on, either stainless or mild steel, just make sure it's the right diameter to accept the front pipes.

The race bikes say leave the bottle empty, but you can half fill it and see how that goes

Yes at the join I have a problem but I dont see any mild steel there. Am I correct in saying the rear header pipes join the down pipes with a flange? This part is ok but there is a join before the down pipes join into one, this is where the problem is, just seems like one stainless pipes fitting in to another. Is there a seal in there or can I just weld all the way around. There is also a hairline crack (bike was crashed) that I will need to weld but need to know the grade of stainless.

One more question, do I have to drain the oil from running temp? I know it would be better but I have the front end off and have drained the coolant so cant start the bike but I want to clean the clutch plates.

RegionX wrote:Yes at the join I have a problem but I dont see any mild steel there. Am I correct in saying the rear header pipes join the down pipes with a flange? This part is ok but there is a join before the down pipes join into one, this is where the problem is, just seems like one stainless pipes fitting in to another. Is there a seal in there or can I just weld all the way around. There is also a hairline crack (bike was crashed) that I will need to weld but need to know the grade of stainless.

One more question, do I have to drain the oil from running temp? I know it would be better but I have the front end off and have drained the coolant so cant start the bike but I want to clean the clutch plates.

Is it a standard exhaust system? / What is your problem?

You can drain the oil with it cold, it'll just take longer. Cleaning the clutch plates? Not seen anyone do that on an NC30 before...

On the standard exhaust the front down pipes join to the rear pipes on slotted slip joints with clamps. Inside the larger flange, which is on the rear exhaust pipes, theres a gasket. This isn't needed on some aftermarket rear-pipes which are a tighter fit.. the Yamamoto I have doesn't need gaskets or clamps but doesn't blow.

On the standard system the flange slip joint / collar is made of mild steel, which is why it rusts off and disintigrates.

Is it a standard exhaust system? / What is your problem?

Not sure if it is standard, my problem is the exhaust system has a few leaks, I have a new TIG welder and would like to sort it out, I have taken a photo and will post it shortly.

I have a bigger problem, checked valve clearances and things got a little weird. On both sets of cylinders the camshaft marks (timing marks I think) were not right, the exhaust camshaft was not vertical at TDC (at T1 and T2). Besides this my inlet clearances were really bad, one inlet valve had 0.37 and another <0.05 (feeler gauge only went this low) on the same cylinder. I double checked all of them and find it hard to believe I could have messed up that badly (I'm sure I'l check again tomorrow). The inlet clearances were all wildly out and although the exhaust clearances were all a bit out of tolerance they were at least consistent. The only explanation I can think of is that someone did it wrong in the past, surely there is no reason inlet clearances on one cylinder would wear in different directions? Also this should explain my poor cold starts and erratic idle, no?

All I can say is fuck! I think I dropped a shim in the engine, going to get a telescopic magnet tomorrow. What are your thoughts on retrieval? Please say I wont have to crack open the engine.

Anyway, 6 of the shims looked as though they had been filed by hand will replace them all as well as most of the others (was able to make 2 successful swaps before dropping the shim, FUCK.

EDIT: I should add that I was doing it in bad lighting and didn't see it fall in the engine (down the center as I left the spark plugs in) haven't had a good look with a torch yet but I fear the worst....

RegionX wrote:All I can say is fuck! I think I dropped a shim in the engine, going to get a telescopic magnet tomorrow. What are your thoughts on retrieval? Please say I wont have to crack open the engine.

Anyway, 6 of the shims looked as though they had been filed by hand will replace them all as well as most of the others (was able to make 2 successful swaps before dropping the shim, FUCK.

EDIT: I should add that I was doing it in bad lighting and didn't see it fall in the engine (down the center as I left the spark plugs in) haven't had a good look with a torch yet but I fear the worst....

If it's in the engine just flush it with some oil, drop the sump and you should be able to get it out (after draining the oil of course)

Not the end of the world but a bit of a pain in the arse job.

Maybe you didn't check the clearnces correctly.. align the timing marks.. if you crack a plug you can put screwdriver in the port to verify the piston is at the top.

The cam lobes don't point directly up if I remember properly.

You'll get there.. just take it slow.. better light, more prepare!

Thanks, definitely didn't measure clearances wrong. 6 of the shims were filed down and completely uneven, old grindy the mechanical clown decided he would make his shims the right size I guess.

When the engine is on T1 or T2 I understand that the timing marks on the cam shafts should be vertical (on the relevant cylinder pair) either facing towards or away from the cylinder. When I do this one of the timing marks is not vertical but slightly off, I'm not looking at the lobes. More specifically the problem is that at TDC the exhaust valves are not fully open whereas the inlet valves are due to the camshafts not being in sync with each other. Is there a way to adjust this? Surely this would also be throwing my clearances out?

Grindy the Mechanical Clown? I think he owned my mate's FZR600 at one point.

Probably, anyway he has cost me a lot of money, 6 unusable shims at about 9 pounds each (R100) never mind the other 10 I have to swap out... I think it will be worth it though.

I am going to start a separate thread about my clearance problems but for this thread I can hopefully sort out the exhaust. I still need to know what grade of stainless the pipes are made from, here is a picture of the join that leaks and needs welding or better sealing?

In regards to the overflow bottle it is just that, fill the radiator up. When it heats up any excess will flow into the bottle. There's no need to put the coolant in the bottle.