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My Locost Carb Balancer...
robocog - 23/5/10 at 03:34 PM

My Locost Carb Balancer... is made from fail as well as other household junk

Not on the car, as my Gunsosns "pea in a graded tube" effort works 100%

But it just will not work on the twin cylinder carbs on the motorbike

It has a pair of vacc takeoffs on the carbs
but it just sucks the pea to the top of the pipe...so no use

So I built a manometer type affair
Just a plank of wood some clear tubing some cable clips and some fork oil

Theory /was/ sound enough

method..
fold the clear pipe in half and clip it to the plank
fill a small quantity of fork oil into the pipework (which eventually settles at the bottom of the loop)
hook both ends to each vacc takeoff
start bike, tweak balance adjuster till both pipes oil levels are as near as damnit

needless to say it has all gone horribly wrong several times already with alternate cyls sucking a gobfull of oil and no happy balance found :-(

Sick of filling the pipework with fresh oil and then waiting for it to settle/ find a level only for one cyl to suck it all out before I get chance to do anything

I'm sure I did this ages ago and got them as close as could be expected but now kicking myself I didn't bother to use the locknut on the adjuster...DOH!

Exhaust is a 2>1 affair so no use in checking they are making the same noise or same pressure out the back as suggested in the manual

Looks like I should have just bought the type with gauges (assuming they will be ok for what appears to be quite a massive vaccum)

Regards
Rob


JAMSTER - 23/5/10 at 03:42 PM

why not try one of these i have one it's ok

http://www.machinemart.co.uk/shop/product/details/gunson-g4053-carbalancer


RichardK - 23/5/10 at 04:23 PM

u2u sent mate..


robocog - 23/5/10 at 04:24 PM

Yup thats the aforementioned Gunsons pea in a clear tube

The pea however just gets sucked to the top when attached to the vacc takeoff on the side of the carb (too much vacc at that point)
I guess I could buy a fishtank valve and a t piece and try and calm it down by bleeding some of the vacc off

For now I have just got it by trial and error so when you pull a plug on one side it stays at the same RPM as the other when plug pulled that side

Kind of crude, but must mean its close ish?

Revs now pick up die down a lot quicker than they were (a good sign I guess?) but could also be because I have also put new points in and a new condenser and timed it to perfection

Regards
Rob


StevieB - 23/5/10 at 06:12 PM

I was shown by a friend (Coose on here) to do it by listening to the carbs using a piece tube in each carb inlet to listen to the sound (like faint bongo's) and dialling in the balance from there.

As low cost as you can get and apparently the preference of a lot of experts.


David Jenkins - 23/5/10 at 08:08 PM

I used a length of tubing for balancing my bike carbs shortly after they were fitted - the aim was to get them close enough that the engine would run reasonably well. When I finally got an airflow meter I found that I hadn't got it quite right - but I was surprised how close I'd managed with the tube.