downpipes and seat

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dunk 1
Posts: 208
Joined: 25 Oct 2007 18:16
Location: cumbria

downpipes and seat

Post by dunk 1 »

Looking for some advice - bike is looking a bit tatty and it's time to treat it to some new parts. Seat first - 9 years ago i fitted a new round bum stop seat and it is now past its best - cover split and the metal trim on one side has come off. Do i get it recovered or buy a new one, is 9 years a reasonable expected lifespan?
Also I need new down-pipes, some years ago I fitted a set of stainless but have never been happy with the fit, eventually removing them as I am sure they contributed to the failure of one exhaust port thread, stuck the old dented originals back on but they are soon going to die. Can anyone recommend a source of good quality, preferably stainless that do fit. NLM do have a 2 into 1 at the moment -anyone any experience of these since I don't want to make the same mistake twice.
As a consequence I do have set of used badly fitting stainless down pipes that someone may have better luck with than me - you'll have to collect or pay postage but since I don't think they are right I can hardly charge.
Thanks Duncan
dunk
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MarkB
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Location: Stevenage

Re: downpipes and seat

Post by MarkB »

I bought some chrome downpipes and seamed silencers from motostoriche italiane. Excellent quality and good value. I've also bought a new Sport seat from Nisa, who made them originally, via Wolfgang Tritsch.
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Steve Brown
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Joined: 12 Nov 2007 23:44
Location: Leicestershire

Re: downpipes and seat

Post by Steve Brown »

MarkB wrote:I bought some chrome downpipes and seamed silencers from motostoriche italiane. Excellent quality and good value. I've also bought a new Sport seat from Nisa, who made them originally, via Wolfgang Tritsch.
Mark, I was after some pipes recently for my 350. I eventually decided to bite the Euro bullet and buy a set from that firm. The next time I went on their website they had been removed from sale! :x
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Steve Brown
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Joined: 12 Nov 2007 23:44
Location: Leicestershire

Re: downpipes and seat

Post by Steve Brown »

dunk 1 wrote:As a consequence I do have set of used badly fitting stainless down pipes that someone may have better luck with than me - you'll have to collect or pay postage but since I don't think they are right I can hardly charge.
Thanks Duncan
Hi Dunk, I saw this when originally posted and was tempted to take up your offer of the stainless pipes. Then I remembered when I last bought Morini pipes from Armours with the same outcome with regard to fitting as yours. Armours refused to accept the pipes were wrong and insisted that my bike was obviously bent. Nowadays I could cut and shut your pipes (or rather get a skilled adult to do it for me) but in the end I gave my scabby old Morini pipes one more chance in the struggle against the hacksaw and mig welder. This time the toolkit won and I have a properly sealed set of pipes for the first time in ages.
Is it not still possible yours could be cut and realigned/welded to achieve a good fit? It's possible to polish out the welds too, on the decent stainless material that Armours can't bend properly.
All donations to the rest home for old Camels, Leicestershire.
dunk 1
Posts: 208
Joined: 25 Oct 2007 18:16
Location: cumbria

Re: downpipes and seat

Post by dunk 1 »

Thank you for your replies. This time the offending pipes are not Armours items (has anyone tried them recently?). To my eye the problem is that one of the stubs for the balance pipes is not at 90 degrees to the main pipe but the other one is - making it very much an interference fit. I did take them back but was persuaded that they had been checked for fit before dispatch and they would settle in - I am an idiot!. The task is beyond me (At the moment would like to learn welding skills but don't know where to start) but there should be someone in Barrow who can do it. If they straighten out the stub though could this put all other alignments out- still its wrong already so nothing to lose.
Would prefer stainless as the bike lives outside under a cover, not sure I trust Italian chrome either - the Sito cans I bought started to rust very quickly. I also preferred the Busso ones the bike came with - much smaller and neater ( does anyone still sell those?)
Thanks - Duncan
dunk
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72degrees
Posts: 1549
Joined: 31 Aug 2007 21:24
Location: West Midlands

Re: downpipes and seat

Post by 72degrees »

If Motostoriche do still supply pipes I'd be inclined to go with them. I recently bought a new pipe for my 57 Gilera 175 from them. A very good fit apart from being a bit tight to get the OEM silencer over the end section that is crimped up, but the bend is perfect. Too early to say about chrome longevity.

My only experience of the NLM stainless 2:1 system is on the 2C/375. It was a struggle to fit, but with a 350 motor in a 250 frame that was always going to be the case. I found the 'Y' piece joints needed clamps to ensure gas tightness but Mikalor stainless ones did the job. I quite like the 'note' and it seems to go pretty well on it.

R K Leighton can recover your seat (they did my 2C one), but I suspect the cost might not be that much less than for a new Nisa one.
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72degrees
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Re: downpipes and seat

Post by 72degrees »

Steve Brown wrote:
MarkB wrote:I bought some chrome downpipes and seamed silencers from motostoriche italiane. Excellent quality and good value. I've also bought a new Sport seat from Nisa, who made them originally, via Wolfgang Tritsch.
Mark, I was after some pipes recently for my 350. I eventually decided to bite the Euro bullet and buy a set from that firm. The next time I went on their website they had been removed from sale! :x
Seems to be there now. They were very helpful when I wanted to be sure I was getting the right pipe for my Gilera.

https://motostoricheitaliane.com/negozi ... orini-350/
julianharty
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Joined: 15 May 2016 16:34
Location: High Wycombe
Location: High Wycombe Area (Bucks)

Re: downpipes and seat

Post by julianharty »

Duncan,
I hope you'll find someone able to adapt/adjust your stainless downpipes. If not, I'd be happy to pay you a contribution to them and also for the postage (I live in SE England). I do have a MIG welder and am happy to experiment with fitting them to my 3 1/2 which currently uses a battered set of downpipes I bought from Italy on ebay (a bit of a faff as many sellers there don't take paypal).
Ciao

Julian
Mepstein
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Joined: 27 Apr 2016 02:38
Location: Newark, Delaware
Location: Newark, Delaware, USA

Re: downpipes and seat

Post by Mepstein »

I had an early sport seat recovered and it cost half of a new one. It looks good but doesn’t look the same as the original one.
A good welder who is familiar with stainless steel could make your pipes fit correctly. They will have the correct welding rod for stainless. It’s true that stainless will soften and move a bit when hot but that won’t fix a part that wasn’t made correctly.

I’m pretty lucky to have a friend who’s a pro welder and can weld stainless, aluminum, magnesium and titanium.
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dunk 1
Posts: 208
Joined: 25 Oct 2007 18:16
Location: cumbria

Re: downpipes and seat

Post by dunk 1 »

SorryI am late replying things have been a bit hectic this week. I will ask around Barrow next week when I am free to see if anyone can do what I need but am concerned that straightening may take them further away from what is needed - Julian I will PM late next week when I have made a decision- thanks for all your replies - Duncan
dunk
harrymuffin
Posts: 292
Joined: 07 Apr 2014 16:06
Location: west midlands

Re: downpipes and seat

Post by harrymuffin »

Why do you need to have the front and back pipe connected other than to stop them from flopping about. When I make my own pipes - in stainless - I omit the cross over as it is simply to abate the noise. The 90deg junction does nothing for gas flow in the sense of an extractor exhaust system. Compare the Competition exhausts on any twin cylinder engine from standard systems: Norton, Triumph Thruxton, Honda fours and sixes, Agusta threes and fours etc. Regarding noise, what noise compared to the illegal exhausts fitted to Farley Havidsons.
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