Standard pipe thoughts

[Sprout]

I've been reading the Scootering magazine article concerning testing of clubman style pipes recently

I'm becoming more and more interested in the idea of reverting back to a standard (if there is such a thing) pipe and enjoying a more sedate ride.

What I wanted to ask was..

What makes that rather dull looking pipe perform so well up to 5ish thousand RPM?

From my (very) limited understanding, the long lead in pipe length and narrow diameter will contribute to good torque characteristics

I'm guessing the rev limitations are governed by pipe diameters both in and out of the body (and the mushroom baffle if fitted)

What else does it have in it's favour? I can't really seem to think of anything much

I suppose most improvements in performance come at the cost of loss of low down torque or noise increase (pushing the power up the rev range)

I'm currently cutting and chopping up a couple of box pipes to have a play (no science really, just saves me watching telly) and wondered if anyone would be prepared to share their thoughts....

[scooterslag]

Be interested to see how you get on with your chopping experiments I'm a big fan of the standard pipe and think many people feel they have to fit a clubman or bigger as a matter of course when they could probably get by ( with a few internal mods) with the standard plumbing

[db67]

Ron Moss Avanti ex box , best clubman i've run

[Warkton Tornado No.1]

From first ownership of Lambrettas, there was much experimentation amongst the few of us locally that were enthusiasts, despite the demise in popularity circa 1973.

With my 'best' GP200 off the road, it was easier to keep mobile by buying a GP150 for a song. However, it was sluggish, so I cut the standard silencer apart & removed the central baffle plate. The tailpipe was shortened to suit.

The result was an improvement in acceleration but also (though I was unaware of the terminology then) the ability to 'over-rev' which can sound a bit frightening even now!

Basically, the restrictions placed within OEM exhausts encourage torque @ lower revs & are conducive to noise reduction. As the many fans of Clubman's are now finding, despite some manufacturer's claims (you know the ones. "clocked @ blah-blah-blah mph by a police car") there is no getting around a restrictive tailpipe when it comes to potentially damaging heat build-up.

So, the 'straight through exhaust' was great on a GP150.

Later experiments involved gutting Ancillotti exhausts with a 25 mm tailpipe on a 'tuned' 200. The result was a cooler, easier revving engine with the ability to over-rev. There probably was a loss of low down torque, but as a regular 'niter go-er weighing all of 11 stone @ the start of a weekend, I can't say I noticed.....

The gutted Ancillottis were noisy, but if you spotted the Feds, short shifting was the order of the day. Kerist! We lived life on the edge

[Sprout]

I finished a pipe today

No mesh or dampening material

The "ring ting ting" resonance of the body of the pipe (and cone I've rolled and welded on) is obnoxious

Best I open it up again and rework it

Adjustable main bracket is a vast improvement