Looking for pipes of peace not pieces of pipe!

[Cliff]

Hello Morinistas
I've been restoring my "77 Strada and have at last come to fitting the exhaust - an exciting step forward, or so I thought!

I bought a new set of stainless steel downpipes from NLM about a year ago but have run into a problem. When fitted up they end up at outrageously different levels and slope angels at the back. ( Sorry couldn't upload the images for some reason)

After a lot of repositioning, playing about with the balance pipe, swapping silencers from side to side, measuring things, wondering about the silencer brackets etc it seems to me that either the o/s front cylinder downpipe upswept section ( at the back end ) is at too great an angle or the rear cylinder downpipe conversely hasn't got enough angle at its end so the n/s silencer runs out pretty much flat with hardly any upsweep! Or could it be a combination of the two? Has anyone else had trouble with these pipes and fitting or is there something I'm overlooking!?

I've fitted Tarrozzi rear sets ( another huge faff in itself) and although they are close to the rear downpipe they don't seem to be interfering with the pipes themselves. The silencers are aftermarket items with no markings. I've got some stainless silencer brackets ( also from NLM) but am quite happy to ditch these and make others if need be. Hope this all make sense, any thoughts or ideas much appreciated.

Cliff

[buell1203]

Why not take them back? Failing that have them bent to shape. You may be able do do it yourself by packing with sand then place in a sturdy vice and physically readjust the set.
If you do. It without sand or a former inside the pipe they might kink.

[Tufftrax]

I suggest checking the exhaust ports for correct seating and also to make sure all traces of the old gaskets have been removed.

I had a similar problem when I first tried to attach new silencers last year and the "wrong" angle was caused by bits of old gasket having lodged themselves in the ports and once removed worked fine.

It wasn't immediately obvious but having a scrape around the port with a small screwdriver in the seating area revealed bits of old gasket (they had disintegrated due to age) which soon came out and solved the problem.

[EVguru]

I've had to modify an least one NLM supplied 350 exhaust. It looked like a 500 pattern had been used for the front cylinder pipe! The owner had had the system for about 4 years (bike off the road) so it was a bit late to complain.

I had to cut about 1/2" out of the front downpipe and about 1/4" out of the port stub, then TIG weld the system back together. The stub weld was hidden and I managed to file and polish the downpipe so the weld there wasn't obvious.

I've yet to come across an aftermarket system that fits as well as an original. I've seen an Armours system so bad that you almost doubt it was made for a Morini! A badly fitting system is often the cause of stripped exhaust threads as people try and 'pull' the pipes into place.

You're really going to struggle to bend stainless pipes. Talk to NLM first.

[Cliff]

Thanks for your input chaps. I've hopefully managed to upload some images albeit of poor quality just to give an idea of how much these pipes are askew.

Not on the level!

pipes.jpg (139.57 KiB) Viewed 7478 times

It has to be too much upswing - EV Guru good point about the possibility of these being for a 500. Presumably these had more of an angle on the silencer.

Swing high sweet chariot

upsweep.jpg (178.34 KiB) Viewed 7478 times

Then the other side seems much better but perhaps almost too flat!

better but...hmmm

rear pipe.jpg (136.68 KiB) Viewed 7478 times

While I realise that restoring Italian bikes from the 70's you expect a fair amount of latitude in fitment - especially when dealing with after-market parts these are massively out - almost back to the levels of BSA and Triumph! I think with the Morini's delicate castle nut and port threads they should be a better fit and can't be wrenched around ( or booted into shape as I remember on my old Starfire!) I'm not keen on cutting and shutting the pipes - these are brand new after all. I'll go back to NLM - these aren't really fit for purpose.

Cliff

[3potjohn]

To me this would make me mad. I do hope you resolve it. I got a left hand pipe only to discover the bend is different (why do this?)so i have given up for now.And to think I once lived near the bloke that made exhaust pipes for James Hunt.
I was going to go down the stainless route but don't fancy blackening them up with barbeque paint, which judging by the weather will be probably not be sold out.(we have a drought warning and a flood warning simultaneously)
I have tracked down some black chrome pipes but am not prepared to share this information.

[EVguru]

I got a left hand pipe only to discover the bend is different (why do this?).

Early pipes have a tighter bend and I think this was opened out a bit for the styling on later bikes.

I was going to go down the stainless route but don't fancy blackening them up with barbeque paint.

You can get a chemical blacking for stainless.

[unreal]

I also believe the the front pipe on later kink frame bike has a different curve as the front frame down tubes come in tighter to the engine.

Simon