Pipes too big by 1mm.

André Bourbonnais · Apr 17, 2018

NortonMKIIA850 said:
+1 on that, that was my experience. A few minutes' filing will show you that it's easy to make these pipes fit, and that you must never buy from Norvil ever again, if you can possibly avoid it.

I didn't buy them from Norvil.

André Bourbonnais · Apr 17, 2018

Bought them from a place here in Canada cause the shipping fees were insane from anywhere else.

NortonMKIIA850 · Apr 17, 2018

André Bourbonnais said:
Bought them from a place here in Canada cause the shipping fees were insane from anywhere else.

Do the pipes have 'N 63' stamped on them near the tail end? If so they were supplied by Norvil, no matter who you bought them from. If not, then we have another source to avoid.

Craig · Apr 17, 2018

Andre , it would be a good service to other forum members if you would name the Canadian outfit that sold you the poor sized pipes , maybe the seller will smarten up ....

kommando · Apr 17, 2018

I have a head with a original thread and a repaired thread, the ID is the same, a thread repair will not change the ID but gives a plausible excuse for Norvil not to replace their stock and not take returns.

André Bourbonnais · Apr 17, 2018

NortonMKIIA850 said:
Do the pipes have 'N 63' stamped on them near the tail end? If so they were supplied by Norvil, no matter who you bought them from. If not, then we have another source to avoid.

N63 yes indeed. Ah crap.

André Bourbonnais · Apr 17, 2018

N63 yes, bought them from Walridge.

NortonMKIIA850 · Apr 17, 2018

When I complained to Norvil about this same issue, they insisted that only their pipes had 'N 63' stamped on them, and asking me about it was their test to ensure that I really had a pair of pipes from them, and was not trying it on – they love to blame the customer; in which case Walridge must be getting these pipes from Norvil. Unless there's someone out there copying Norvil ... But don't despair, either return them with an explanation and get a pair that fit, or get your file out and reduce the radius of the flanges by 1mm all round, you might be surprised how easy it is, I certainly was.

André Bourbonnais · Apr 17, 2018

NortonMKIIA850 said:
When I complained to Norvil about this same issue, they insisted that only their pipes had 'N 63' stamped on them, and asking me about it was their test to ensure that I really had a pair of pipes from them, and was not trying it on – they love to blame the customer; in which case Walridge must be getting these pipes from Norvil. Unless there's someone out there copying Norvil ...

Well see what Walridge says.

850commando · Apr 17, 2018

there ya go ; with more info problem solved, sort of... LAB; i have no time on 72's ... thats my excuse for running of half cocked...

André Bourbonnais · Apr 17, 2018

I was told to grind to fit by the supplier. I'm pissed. I shouldn't have to spend more time and effort fixing their mistakes. I don't go buy a car then they say we don't have it in black but here's a paint can.

Time Warp · Apr 17, 2018

That's a flakey supplier to say the least.

Why can't the threaded lock ring bores be chucked up in a lathe to bore the ID a little to take the pipes ?

Mr. Rick · Apr 17, 2018

André Bourbonnais said:
I was told to grind to fit by the supplier. I'm pissed. I shouldn't have to spend more time and effort fixing their mistakes. I don't go buy a car then they say we don't have it in black but here's a paint can.

They didn't even offer you a file. I'd be upset, too.
Literally not "fit for service", they shd be returned for a full refund. Or send them back and let them do the filing themselves.

Ron L · Apr 17, 2018

André Bourbonnais said:
Original is 73mm and new one is 74mm.

Really??? That's as big as the cylinder bore!

I had a similar issue with my P11 hi pipes. I have 3 sets from different suppliers. Two of the sets would not fit in the head until I ground down the flange. The set that didn't was bent wrong, the right pipe would not clear the tach cable and the left pipe interfered with the primary cover and battery cover. I had to take a left pipe from one of the remaining sets and right pipe from the other to make a set that fit reasonably well. Most Commando pipes I have needed slight tweaking to fit without straining the rubber mounts. Seems too common with pipe makers.

André Bourbonnais · Apr 17, 2018

Ron L said:
Really??? That's as big as the cylinder bore!

I had a similar issue with my P11 hi pipes. I have 3 sets from different suppliers. Two of the sets would not fit in the head until I ground down the flange. The set that didn't was bent wrong, the right pipe would not clear the tach cable and the left pipe interfered with the primary cover and battery cover. I had to take a left pipe from one of the remaining sets and right pipe from the other to make a set that fit reasonably well. Most Commando pipes I have needed slight tweaking to fit without straining the rubber mounts. Seems too common with pipe makers.

It's a typo.

André Bourbonnais · Apr 17, 2018

Ron L said:
Really??? That's as big as the cylinder bore!

I had a similar issue with my P11 hi pipes. I have 3 sets from different suppliers. Two of the sets would not fit in the head until I ground down the flange. The set that didn't was bent wrong, the right pipe would not clear the tach cable and the left pipe interfered with the primary cover and battery cover. I had to take a left pipe from one of the remaining sets and right pipe from the other to make a set that fit reasonably well. Most Commando pipes I have needed slight tweaking to fit without straining the rubber mounts. Seems too common with pipe makers.

The rubber mounts is my next issue. The angle us wrong. We're not only mechanics but also fabricators. Lol

mdt-son · Apr 18, 2018

NortonMKIIA850 said:
But don't despair, either return them with an explanation and get a pair that fit, or get your file out and reduce the radius of the flanges by 1mm all round, you might be surprised how easy it is, I certainly was.

If the diameter is 1mm to large, I would reduce the radius by .5 - .6mm to start with ....

-Knut

NortonMKIIA850 · Apr 18, 2018

mdt-son said:
If the diameter is 1mm to large, I would reduce the radius by .5 - .6mm to start with ....

-Knut

Yes, that would make sense, but I'm pretty sure I took mine down by 1mm, reasoning that that would give 0.5mm clearance, making for an easier fit – but of course YMMV! Anyway my pipes are nice and snug like that.

André, Walridge didn't say where they got the pipes from? I'd be interested if they confirmed the Norvil connection. Aside from the pipes not fitting the head, they fitted fine, and didn't require any massaging to line up with the silencers. Very poor service anyway.

Danno · Apr 18, 2018

Bob Z. said:
As a side question, does an exhaust port thread repair reduce the inside diameter of the port?

Shouldn't unless the person doing the repair expects you will use a differently-threaded collar than stock.

André Bourbonnais · Apr 18, 2018

NortonMKIIA850 said:
Yes, that would make sense, but I'm pretty sure I took mine down by 1mm, reasoning that that would give 0.5mm clearance, making for an easier fit – but of course YMMV! Anyway my pipes are nice and snug like that.

André, Walridge didn't say where they got the pipes from? I'd be interested if they confirmed the Norvil connection. Aside from the pipes not fitting the head, they fitted fine, and didn't require any massaging to line up with the silencers. Very poor service anyway.

They offered me a full refund but I decided to grind them down a bit with my Dremel now they are perfect.

Mike replied with this,

We don;t get pipes from Norvil, they are either TJ Wassell (stamped N63 at the ends) or LF Harris stamped 06 3375/6.

Mike has always answered all my questions and Walridge have been good to me so I didn't make a stink.

Pipes too big by 1mm.

.......back to the 70's.