Removing Baffles Le Mans I / II Silencers - anyone done it?

[Simon_London]

I would like a less restrictive exhaust silencer on my G5 Cafe racer. (36mm carbs, ported, fast cam and lightened flywheel, Keihan Le Mans I/II silencers).

I have a spare pair of Keihan stainless Le Mans I /II silencers. Keihan will remove the end cap, and take out the baffle and replace the end cap with a one that has a larger exit hole for £100. They will be unable to remove the proximal baffle which they estimate conributes 30% of the flow restiction.

I have large bore stainless down pipes (42mm) with a cossover and a 38mm stainless H Pipe.

Replacing with a Lafranconi sytem will be expensive and will rot in time (not sure how long they last), so a cheaper compromise would be removing the rear baffles of the Keihan silencers.

Any thoughts on performance and sound?

Cheers

Simon

[PeteS]

Are these copies of the original 850 LeMans mufflers? If so back in the day we drilled 1/4" holes in a circular pattern  centered halfway between the exit hole and the outside edge. The stock exhaust is very restrictive.
This did help a bit but I don't think you want to completely remove the baffle. Any bike I did that to lost power. You need a certain amount of back pressure.
What made a significant difference is the Rennsport 2-1-2 exhaust. POS workmanship but great performance.

Pete

[Simon_London]

Yes they are Le Mans replicas in stainless.

Think I will bite the bullet and buy some Lafranconis and sell the spare silencers.

[canuck750]

This is how the exhaust on the 77 Le Mans I bought last spring looks like. I take it the holes are not stock?

It sounds real nice though and I noticed the increased low end grunt that my V7 Sport is lacking.

[Simon_London]

Yes non standard holes! Anyon else running his mod?

[Stevex]

I bought some original Lafranconis which were rotted and dented at the back end. I cut out the damage and had the backs rewelded on. The process removed the main baffle. Sounded nice at idle but after running them for a couple of weeks I refitted my set of Keihans. The modded 'conis sounded like a Lancaster on its take off run. I may try them again next spring.