1000 3c 180?: down pipes & collector with 38mm bore

iLaverda

iLaverda

New member
Location
Hamburg / Germany
Looking for a set of down pipes (manifolds) and a collector (3-2) with an inner diameter of 38mm for my Laverda in normal steel chromed or INOX which fits with the original main stand.

Any any leads to an immediately available set would be great; I am located in northern Germany.
 
https://www.ebay.co.uk/itm/LAVERDA-38mm-LARGE-BORE-DOWN-PIPES-COLLECTOR-1000-1200-NEW/132861093327?hash=item1eef2365cf:g:48MAAOSw~JRaosZ3

I think it is Malcolm Cox advertising these.
 
@ helicopterjim: I contacted the eBay-seller roadrat73 today and he confirmed that 38mm stands for the outside diameter; the bore is 35mm.

That means I am still in quest for the right set.
 
I have a set of big-bore headers and collector plus his billet header flange head clamps from Red on my 3c, there was a limited number available back then. Maybe he had more made?
 
iLaverda said:
@ helicopterjim: I contacted the eBay-seller roadrat73 today and he confirmed that 38mm stands for the outside diameter; the bore is 35mm.
Click to expand...

I believe the ones Malcolm sells are the same at 38 OD and 35 ID ..... stock pipes are 35 mm OD but not sure of ID. I don't know of any 38 ID readily available.

Jim
 
helicopterjim said:
I believe the ones Malcolm sells are the same at 38 OD and 35 ID ..... stock pipes are 35 mm OD but not sure of ID. I don't know of any 38 ID readily available.

Jim
Click to expand...

Man you'd be needing some series port work to justify 38mm ID pipes otherwise what would be the point ... 38mm Id seriously that's crazy..but what would I know
 
Brett said:
Man you'd be needing some series port work to justify 38mm ID pipes otherwise what would be the point ... 38mm Id seriously that's crazy..but what would I know
Click to expand...
Well some of us need  them...
 
Pretty sure my SFC factory 2/1 system had 38mm ID headers - a 1200 hi-comp triple would surely need to breathe as well, so doesn't sound absurd to me. Personally, I'm going smaller ID headers on the SFQ as modern thinking is about exhaust gas velocity fro a certain distance exiting the ex port.

The cheap replica SFC 2/1 sys I had on my motor (basically SFC spec) had smaller ID headers and it breathed very nicely indeed.
 
Not sure how modern the thinking is about exhaust gas velocity Quentin. Phil Irving talks about exhaust gas velocity in "Tuning For Speed", first published in 1948. He's a bit vague about it though, and doesn't offer any formula for working out the optimum pipe size for a given set of engine specs. He just gives a table of recommended exhaust dimensions for a bunch of different engines - all of them relevant to the era in which the book was written (old pommy bikes) so not a lot of help to us.

I have a set of Red's 38mm headers on my Jota. They were a definite improvement over the 3-1 system that was on the bike when I bought it (as confirmed on the dyno) but I dunno how they'd compare with a stock system, which is something less than 38mm. I'm unable to offer a comparison because my bike has never had an original exhaust system during my ownership.
 
try these books, about 30 pages of highly technical stuff on exhaust headers alone, OK, so the three into ones that I depict are for a three port, four cylinder Austin, but just as an aid to what lies inside, not an idea for triple cylinder Laverda's
CLEM
 

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