Hi all, just picked up a bromlech 3 into 1 exhaust for $50! looks great, just needs a sand and a respray with the bbq black spray paint! here is the question:
Do I have to do anything to the jetting if I only change the exhaust? I am keeping the stock air box, filters etc. someone told me that no changes are necessary with a pipe change, only if the air filters are changed or the air box is modded.
any suggestions would be great.
Thanks
73 gt550 with bromlech 3 into 1 jetting suggestions?
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Re: 73 gt550 with bromlech 3 into 1 jetting suggestions?
Just my 10p worth, but my 380 ran a little rich with a Piper 3-1 (stock carbs, airbox and filters). I got it dialled in with a tweak of the pilot screws and removing the snorkel from the back of the airbox.
I think it's highly unlikely it will run lean with the 3-1 and stock everything, but as I say, just my 10p worth ...
Be prepared for a bit of fiddling when mounting the 3-1 to the exhaust ports in the cylinders ... three hands are useful
. I sorted it using fresh exhaust gaskets with a little silicone sealer, then offered the pipe up and mounted it with loose bolts, then tightened the exhaust flange for the CENTRE cylinder (to 'square' the exhaust mouths into the ports), then gradually tighten the other two exhaust flanges down snugly, then finally the frame mounting.
Good luck, enjoy the noise
I think it's highly unlikely it will run lean with the 3-1 and stock everything, but as I say, just my 10p worth ...
Be prepared for a bit of fiddling when mounting the 3-1 to the exhaust ports in the cylinders ... three hands are useful

Good luck, enjoy the noise

1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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Re: 73 gt550 with bromlech 3 into 1 jetting suggestions?
Thanks Craig, good info. will let you know how it turns out. just waiting for the bike to arrive from america in the next few weeks, bought the pipe today as I got a smoking deal on it.
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Re: 73 gt550 with bromlech 3 into 1 jetting suggestions?
Mike, there's a couple of members on here in OZ with that pipe on a GT750. You might try PMing them directly.
In their adverts back in the day, Bromlech claimed that stock jetting worked fine.
In their adverts back in the day, Bromlech claimed that stock jetting worked fine.