Synchronising Throttle Bodies

Hi, Im am going to check (and likely adjust) the valve shims over the break and I was just doing abit of reading on some sites and they say you should sychronise the throttle bodies at the same time. Reading further it sounds like this is a bitch of a joib, needing special tools and computer software. Anyone had this done or done it yourself? any idea what the kawasaki dealer would charge? I was going to strip it down and take it in to have the valves checked anyway.

Thanks
Ben

It's a bit fiddly to do, but not high tech at all. Probably the hardest bit is setting it up so that it can run without the tank in place - harder for you fuel injected guys, not so hard for carbed bikes:


You want to equalise the vacuum in each throttle runner. I used to have a bottle of mercury (explains a few things!) and just put each or the four tubes into that, but now (think of the children!) I use a set-up with diesel, and tee-d them into each other, so you need to equalise each pair of tubes:


One mod I want to do is to put a small (~1mm) jet into each tube to smooth it a bit - the fluid level is a bit jumpy at idle.

(-8

diesel - that's an interesting idea. A few blokes I know who have made up their own manometers use auto trans fluid.

Mercury resists the problem you get at idle with the big fluctuations - but its not something you really want to be dicking around with.

Mr Faulty - do the valve-clearances first, so the engine is pulling the right amount of air through each cylinder. Then do the balance. Not the other way around.

Fantastic, thanks!

to dampen the bouncing gauges i use small irrigation taps available from just about any hardware store for about 60 cents each and a couple of polly risers as adaptors on the old suzuki the adapters go into the intake manifolds so the pionty polly adapters screw straight in on the 12 i have 4 vacume hoses in place numbered and pluged just pull them outone side unplug em connect the gauges adjust the taps to dampen piece of piss really i tried to upload pics but its much easier to do the job than resize the photo

Last edited by mick12 on Tue Dec 24, 2013 9:51 am, edited 1 time in total.

Thanks for the reply everyone. Anyone have any idea how much it would cost to have it done - I will be stripping it down and checking the valve gaps

Another thought, per the FCRs I used to run on the old ZXR, I synced my TBs by eye (bought a spare set, pulled them apart to remove the secondary butterfly shaft and servo, hence they needed syncing). From memory there's a single screw between the two pairs, turn the idle screw right down so that there is a tiny crescent of light under the butterfly,and it's very simple getting a 'close enough' match - 'close enough' for me as the bike is a trackie only, hence a rough idle is not of any concern.

Cheers,
Brian

Hi again. I have just spoken with a mechanic at kawasaki and he said the simplest way is to purchase a vacuum guage - from supercheap ebay etc.

Has anyone adjusted the throttle bodies using one of these and is it fairly straight forward?

Thanks
Ben

Nope - you need a specific vacuum guage for a bike- someone I know (ahem) bought 4 car ones years ago with no dampening and the needles jumped around like crazy- of no use at all. Best thing- buy a morgan carbtune- cheap $180 or so last time I checked, and tough- mercury gauges break really easily- had two sets before the morgan. Never again.

As above "Morgan carbtune"...$124.00 oz... delivered from Belfast. http://www.carbtune.com/

Thanks, just found a bike mechanic who said he'll do it for $100 so might get him to do it and if it makes a notable difference, then I'll buy the correct tool and do it myself next time.

Thanks again
Ben