Solid mount V Rubber mount

[mawso]

I've seen written or heard mentioned that solid mount carbs cause petrol to froth...but if the manifold moves with the engine then why is that any different to the carb waggling around on a rubber mount?

I say this as I'm running a solid 28 PHBH at the moment and was going to upgrade to a rubber mounted PWK 30 or even just a rubber mounted 28 PHBH as I saw it as an improvement in some way!

But after seeing my mates carb fall off twice recently, once on the motorway I've decided if it works just leave it.

Although, is there a strong argument to "upgrade" to a rubber mount?

[thackers]

I've never had problems with fuel on either of my solid mount Dellorto's, but then i dont get up to the flat out speeds you Pornstars do

[coaster]

I would suspect that the it's to do with the frequency of the vibration, the higher frequency produced by the engine would be more likely to cause frothing than the waggling about due to suspension movement.

As for rubber mount carbs falling off, it does happen and rubbers do split but there are now better rubbers on the market (MB). I have been running a ScootRs PWK 28/30 for around 5.5k miles and it's still on the rubber it came with. The PWK is very light mind, a mates Spaco was much heavier and was always falling off.

[col265]

My mate runs an iron 225 with a solid mounted 30 phbh and a clubman. He's never had a problem with it and the engine's no slouch I've been led to believe that if your engine revs on a lot more, if you use an expansion, then there may be a problem. Don't take my word for it though

[byron]

I have a rubber mounted VHSA. On the first ride after removing it for whatever reason, it always seems to fall off within a few miles. This happens no matter how carefully I fit it, remembering how it was, checking location of clips, not too tight, not loose etc. So I'll refit it at the roadside and it'll be fine for 00s of miles until i next need to remove it...