13 replies to this topic

[AlexP]

I need to balance my twin HS4's accurately - can anyone recommend be an affordable flow meter type?

[tommy13]

I need to balance my twin HS4's accurately - can anyone recommend be an affordable flow meter type?

Apart from the obvious 2 foot piece of garden hose, there are 2 main contenders. This type
http://cgi.ebay.co.u...=item43a2e1a4e5

And this type
http://cgi.ebay.com/...sQ5fAccessories
I have used the first type which is very good but a little more expensive at around £35. To see the second type being used look here, appears to work perfectly well.
http://www.youtube.c...751E1396854887A

These often come up on Ebay UK, search for carb sync, Uni-syn, carb synchroniser, carburettor balancer.

Edited by tommy13, 15 February 2011 - 09:20 PM.

[bmcecosse]

It really IS easy with a length of flexi pipe and your ear!

[Yoda]

definitely use an earole and pipe. The human ear is a finely tuned and calibrated piece of equipment.












Unless you are deaf of course!

[lrostoke]

Depends how many Motorhead gigs you've been

[dklawson]

If you don't want to use the hose method and want to balance carbs on the cheap there is another method, pointer wires.

See this link below. Scroll about 1/2 way down the page to the picture UNDER the picture of the Unisyn tool.
http://www.sw-em.com/su_carbs.htm

Basically you put a dowel with a bent wire in each carb's dashpot oil reservoir. With the engine stopped and the carb pistons resting on the bridge you point the wire tips directly at each other (but not touching). You start the engine and adjust the idle screws on each carb to the desired speed while maintaining the wire positions so they still point at each other. Then you tighten the carb linkage as normal so the carbs will operate in unison.

[finch661]

homemade one =>

[micromontenegro]

I like my UniSyn very much.

[Big_Adam]

Having a slight bit of tinnitus and gummy ears I use the "Weber Dellorto SU carb Synchrometer balancing tool SK" one, I tried the gunson ones and found it to be utter crap.

So if you want one, I'd suggest the Synchrometer one. If you got good ears, then go for the pipe thing.

[AlexP]

Cheers all - I have tried the hosepipe method, but with no way of validating what I hear I have no idea!

Think I'm edging towards the Weber one as mentioned - cheers.

It says it goes down to 40mm carbs, HS4's are smaller - is this still ok?

Edited by AlexP, 16 February 2011 - 04:52 PM.

[icklemini]

but with no way of validating what I hear I have no idea!

The same noise (suck) through both inlets....

[micromontenegro]

After 20 years plus of synching Zenith-Strombergs by hose and ear, and thinking I had it all figured out, I got the UniSyn "just to see". The results were eye-opening to say the least. Either my ear is not that finely tuned, or the manuals were right when they said you needed a tool!

[lapider]

how exactly do you tune a carb with a bit of pipe

[Big_Adam]

how exactly do you tune a carb with a bit of pipe

You don't, you balance them. Listen to the air rushing past, match it on the two carbs, then keep working down to a good idle speed. Good idea to do mix first as changing mix will change idle speed revs or current ones anyway.