Stepped Manifold Rubber for TS1?

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Adam_Winstone
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Hello all,

I've tried to find an old thread that was on one of the forums but can't locate it... so starting another.

Right, I want to find a stepped rubber that fits the standard original TS1 manifold at one end but takes a 30mm Dellorto the other. Which Dellorto you may ask as the locating rib sits at a difference distance from the stub end between models of the same diameter, i.e. the locating rib of a 30 PHBH is not the same as that of a 30 VHSA? Well, the real answer is that I want to buy one of each so that I can enjoy thousands of trouble-free running without my rubber splitting or my carb forever popping off the mount when the rubber gets hot and soft :evil:

A good dealer that satisfied a mate's requirement a year or more ago, used to supply a rubber that was perfect for the TS1 to 30 VHSH conversion, however, I understand that the ones that they now have are plain on the smaller diameter end. Whilst this would appeal to some, as it physically allows you to fit either a PHBH or VHSH to the small end, with no chance of getting the rib in the wrong position, it doesn't provide the rib in the right position. Having tried the plain cut hose connectors a couple of times on other motors, I really don't like plain ends as you have to do the clip up too tight to stop the carb from falling out, which leads to premature splitting/air leaks. I've tried all sorts of ways to cure plain use (fitting dry with bonding agent, excellent wide flat clips with rolled edges, etc.) but they just don't work for me. However, I have decades and many thousands of miles use of correct rubbers with correctly positioned locating ribs, without splitting or carbs falling off, and now want to source something to satisfy this need.

The manifold in question is a special manifold so I not looking to change manifold, however, I would love to find correctly stepped rubbers, with correctly spaced ribs for a certain carb, that allow me to try a range of carbs on the same manifold/motor. Knowing that there are lots of people out there running TS1s with PHBH and VHSH carbs, where are you sourcing decent stepped rubbers from?

Wasn't it great when VHSAs fitted the standard TS1 manifold and standard rubber :)

Cheers for any info that you can offer on where you have sourced stepped rubbers from (with correctly spaced ribs). I'm not going to get involved with debates over whether I should be using plain rubbers or cut hose, or buying other manifolds... not interested, been there and got bored of sub-standard parts in a very short period of time :roll:

Ta

Adam
gaz_powell
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Adam

try allens performance - they have good pics/dims

http://www.allensperformance.co.uk/prod ... folds.html

I had a pwk on a 34mm mb manifold - rubber came them

Gaz
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carlos fandango
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Readspeed do (or did) the stepped rubbers i use one an a TS and an RB both with PHBHs i dont have any problems with the popping off :) or splitting :)
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Adam_Winstone
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Ta :)
shocky
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When it says to fit flange what does that mean ? Ive struggled to get a rubbet that im happy with ive got a pwk that has a 34.6 mm stub and the manifold is 33.45mm I gor a mbd short manifold as I was told it would fit and thats 36.3 mm the Groove is approx 5mm on the carb and 5mm on the mb manifold and 11mm on the scoot rs one any ideas
sorry for thread hijack
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Adam_Winstone
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No problem about the 'drift'... I know where you are coming from with such fitting issues.

I'd need to know the context of 'flange' (OK, stop giggling some of you!) as it might be about a flange type manifold, where one end is flange fitting, like the old Amal type fitting, rather than hose type fitting at both ends.

Or... it might be used to describe the central raised area in the middle of a rubber mount, where the 2 ends (carb and manifold) butt up against.

I have regularly put my own rib location grooves into manifolds and carbs to allow the rubber mount's rib to locate correctly, simply because I couldn't get the right rubber and don't like the function of the plain hose type. Providing you measure well, mark up accordingly, then start the groove accurately with a fine file or junior hacksaw blade, you can then work around a round needle file until you have a suitable groove in the right place. WORD OF WARNING though - don't go too deep with this groove though as you risk breaking through into the carb stub or manifold bore!!! The groove does not need to be too deep to function well so be cautious if you decide to do this... and don't do it if your toolkit consists of one big hammer... this needs accuracy and care.

Good luck getting your issue sorted.

Adam
Adam_Winstone
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Quick update:

Best rubber sourced so far for my needs is a TS1 to PBHB stepped rubber from MB. As I've modified my VHSH stub to also have the PHBH rib location, the MB rubber fits a treat, is considerably shorter than the other rubbers I've sourced and is nice and strong, whereas others are a bit floppy. The worst of the rubbers I've sourced has the ribs in both end in the wrong place!

Another very good option, which I was put onto by a mate, is the Allstyles machined alloy conversion stub that is a tight fit onto the VHSH stub and increases the O.D. to the same size as the standard TS1 manifold size and has the rib groove in the standard TS1 location. My pal has been running one for over a year, along with the standard TS1 rubber, without issue. If I planned on using a VHSH on a TS1, rather than my current quick testing of various carbs, I think I'd go down this route.

Ta for the comments though.

Adam
shocky
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Adam what position is the rib in relationto the center dont take it of to measure thoughonlyif handy
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gaz_powell
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I've just swapped to a phbh on my ts and opted for the mb stepped rubber to use the fitted mb manifold for 34mm carb

Have to agree the quality and price are good.

The one I had on for the pwk works with phbh and will do a spare to carry

I see AF do a stepped one - no experience.
dodobeckam
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mike at torbay lambretta does the mb stepped rubbers.
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