Ok - no need for an O ring. Just took it out, and it works fine - no vac leaks and their associated rise in idle speed.

When I took it out, I noticed that it wouldn't have mattered if it has sealed or not anyway, as the adaptor plate isn't entirely flat!

Easier fabrication, less prone to vac leaks and better stopping power. What more could you want! :)

Just to throw a spanner in the works.................


Jason, would an 8" booster fit in the width of your Sportster?

I've had a look in my Cabrio, and with the M50 there is no way I can fit anything bigger than the 7", but you may have a little more space?

Marginal.

Measuring it up, there's a 1/4 inch spare at the point where the top of the bonnet side panel meets the servo - and that's not at the widest part of the servo...

You'd have to notch the side panel for it to fit - at both of the stepped sections of the servo. I don't know how much longer it is, but in my situation if it got any longer I may have an issue with my braided lines.

Here's a link to some chrome 7" servos on eBay:

http://www.ebay.co.uk/itm/Zinc-Power...#ht_924wt_1195

They're £30 quid more than Dukesville... And it looks as if the vac inlet is in a slightly different place.

I've spoken to Paul at Ducksville Speed shop, and he has none in at the moment. He would not normally have re-ordered until March / April next year until the new Hot rod season.
However, if enough people commit to ordering he can order a batch (he buys 50 at a time, but does not want 49 sitting in stock over winter) and he would do a modest bulk purchase discount.

So how many are now genuinely interested at £65-£70 each delivered for a zinc finish?

Not sure what the cost would be for Stainless (Paul advised steering away from Taiwanese chrome! and Stainless is a similar price)

I am - count me in. If the stainless aren't too much more expensive, I'll have one of those. :)

I haven't got to the stage of experiencing the 'bum clenching' braking performance of the Metro servo yet but £70 for better braking sounds like a worthwhile investment to me. Put me on the list. I'll have one. Zinc or stainless.

Nigel

I've posted this on the MOC forum as well, to drum up some more trade. More the merrier, and more possibility of getting the order in sooner.

http://www.marlinownersclub.com/foru...d=20765&cat=99

Me too.....

Robin

Dual servo interested
 

Me too. Definitely want one in "Zinc" not SS! Pete.
P.S. They say zinc but it looks like cadmium plating to me. Is that just an American / English language thing?

Good idea...

Mike,
please put me on the list, plated will be fine for me.

You could also hint to Paul that he puts a small advert in CKC and sends a press release to Steve Hole at totalkitcar.com
thanks

Peter

P.S. i guess ebay will then be flooded with metro servo's :lol:

Mike. Where did you buy the long clevis (I assume that I will need the same for my Hunter)?
Also what clearance did you set between the servo adjustable plunger and the master cylinder piston? Peter.

Thanks for trialing it Jason.

Please add me to the list for the plated version.

Peter

I found them advertised on Ebay from a company called Illston & Robson.
They sell a pack of 4 for under £13.
Search "clevis 3/8" UNF".

Again, if we get enough committed orders I can collect a batch from them as they are local to my Birmingham office, and get a better deal.

Peter
I have not even got my car built or on the road yet, so can not comment on the clearance, but I would expect it to be exactly the same as for your current Metro servo. You can determine this by measuring the depth of the plunger in the master cylinder and the servo push rod position relative to the joint face. Then allow for the thickness of the adaptor plate - if you need one and set the gap to be the same as before.

Jason has road tested the Dual 7", so may be he could advise you better?

Pete

I have given the idea of making an adaptor plate some thought.
My concern is that there may be owners with different master cylinders and different fixing hole centres and angles.

However, may be a way round this is to make a batch of adaptor plates with the large centre hole, and the two holes to attach to the servo, and the cut out for the vacuum elbow: but not include the master cylinder fixing studs.
Each user could then drill two holes to match their own master cylinder, and fix with counter sunk set screws? There is no need to ensure a vacuum seal, so as long as the screws are seated below the face there will be no problem.

Is anyone interested in this option?

I don't know what the cost would be, but if I can get 10-15 made locally they shouldn't be too expensive in self colour.

Thanks Mike, I would like to go with that option as well.
Hope it generates enough interest to make it worthwhile.

Guys,

I have not even started yet but I am going to need one eventually so count me in too. Not worried about the finish. I would go for an adaptor plate too.
John

Count me in for a 'univesal' adaptor plate.

Thanks to Mike for pursuing the idea and to Jason for finding the source and for the trial and testing phase. Well done!!

I just set it to suit the master cylinder with the adaptor plug / pin I had. It was actually set a bit higher than the original metro plunger - I just fiddled around with it until I could bolt the cylinder on without any resistance from the piston.

As for the ordering - If it's going to be an issue, I'll just had a zinc / cad plated one rather than a SS one...

Well, could this be the manufacturer?

http://www.mbmbrakeboosters.com/

I downloaded their Catalogue and I'm still drooling. It makes me want to build a hot rod!! :madgrin:
Just take a look at all the adaptors and things !!

Their Technical manual is also quite interesting bedtime reading.....

Count me in for a universal adaptor plate please. Also for a 3/8 UNF clevis too.

To echo Peterux’s comments a big thank you to Jason & Mike for such rapid progress in evaluating this excellent and much needed upgrade. Peter.