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Nolan
8th April 2006, 14:06
Hey
Im just about to buy a carb balancer. I think its an analogue type one, $149 from motomail...
I dont understand where the manual says to put the pipes from the balancer.
And will i need any special extra fittings for my MC22?
I've already flushed the carbs with cleaner but ive put them majorly out of balance:slap:
Thanks guys

T.W.R
8th April 2006, 14:36
Just brought a Mercury vacuum gauge balancer to do my ZXR, its a Motion Pro & cost $160. Mercury gauges are a lot more accurate than dial gauges (FWIW).

The gauge comes with 5mm adapters for most inlet manifolds ,Honda and Suzuki (5mm thread screw-in towers) apart from Yamaha (6mm threads). so you shouldn't need to worry about additional purchases.

The vacuum gauge hoses/adaptors either push onto towers or thread into couplings on the intake manifolds between the carbs & cylinder block.

paturoa
8th April 2006, 16:23
MC22?? - Honda 250????

I've really only had result on CV carbs using balancers.

Normally there will be some little allen key bolts on the engine side of the tubes that the carbs connect to. These almost always have the same thread so the standard little brass tubes (normally) that come with the gauges will fit. There will normally be 2 long ones and 2 short ones. Take out the allen key bolts and the adapters screw into these holes.

Make sure that you assemble the gauges correctly with the restricters in line.

Warm up the bike and keep as upright as possible when testing.

Now is the important part. Find somewhere on the web that tells you what to adjust on the carbs and how many revs! Dont play with anything, especially the pilot jet adjustments or air screws it you dont have to!!!.....

Some carbs you can adjust (eg the butterflys) easily some are real pigs to get at. Have a good look and make sure your tools can do the adjustments before you warm up the bike.

When you are doing the tweaks
- get a sharp sharpie and mark the adjusters BEFORE you do anything. That way you can return to the current.
- only change one at a time.
- only do little adjustments, eg 1/16 of a turn.
- lightly blip the throttle between tweaks, never rev the engine.
- regularly redo the restricters - very important - you'll see.

If they are all already close to each other, then you probably wont notice any difference.

If one is hugely different to the others then get a compression test done first before you change anything. If you haven't got a compression tester at hand then remove the spark plug cap of the offending pot. If the vaccum changes a lot for that pot then it MAY be ok. Check a whole bunch of things before you start playing with the balance including compression, carb seal, float level. If it doesn' change much then you more than likely have a bigger problem.

(If you have slide carbs then the best solution is to remove them from the bike and use 2 nails, say 2mm, and set the slide heights that way)

Have fun.

Nolan
8th April 2006, 17:07
Ok ive got the synchronizer now but i still cant seem to find any alan key screws or anything that looks like i could screw in the sync screw in things.
It has 2 long ones (180mm) and 2 60mm smaller ones.
Which side of the carbs should i be looking at?

paturoa
8th April 2006, 17:32
Engine side, on the intake rubber tracts thingies.

What sort of carbs?

Why do you think you need to balance?

paturoa
8th April 2006, 17:37
is their sale still on??

just the advertised stuff or more things?

paturoa
8th April 2006, 17:46
just googled and found this

http://www.cartestsoftware.com/fz1/carburetorsynchronization.html

and it refers to other sites as well

Cheers

Nolan
9th April 2006, 00:35
Ok thanks for the help guys.
I managed to do it after cafefully rethinking what the manual said and looking at its stupid little diagrams.
The vacuum line from the tank is the first carbs line. there are 2 nipples (#2&#3) right underneath the carbs and last one was a screw plug which i took off and put the screw in type thing(#4).
I've got all the gauges all perfectly even and its idling nicely :).
Just did a radiator flush to.
Cant wait to go for a ride tomorrow:ride:

On another point my dad has been going on about how i dont need new spark plugs but i should be setting the gap?
How do set the gap on a spark plug?

paturoa
9th April 2006, 06:55
Your Dads advice about regapping plugs is sometimes OK.

If the bike is running rich, carbon and other shite will build up, normally causing a high rev miss. Regapping will make no difference. If its running lean then the plug will be dead and your bike will too if nothing is done.

Best bet for a new bike and if you are playing with carbs is to buy new plugs or vinegar them if they are fouled.

I normaly gap using my eyecrometer by either using a small flat screw driver to open the gap or tapping to close. I do it to about that much, see I'm holding my fore finger and thumb apart.....about 1 mm or even a squeak less. What does your manual say?

You can buy a multi blade feeler gauge for the right gap or there are other things with wire loops on. My preference is a feeler gauge but I havent used one for years for plugs.

I use 2 sets of plugs and vinegar to clean them when tuning carbs to get the mixture right.

Vinegar has a low strength acid in it as is excellent for cleaning plugs. Get a plastic jar like an old marmite jar with a lid. Fill about half way with vinegar and gently put the plugs in. Lid on and tip it a little to get the bubbles out of the end. Leave for about 24 hours and then wash well and use wd40 or CRC. The vinegar eats a little of the upper glazed ceramic but that doen't matter.

For your ride today, check the plugs to make sure not running lean after your adjustments.

Cheers

Nolan
9th April 2006, 22:46
How am i actually supposed to read the plug to see whats happening, ive read about how to but explained by a nz'er would be better :).
I think its running lean. Im going to gap the spark plugs and turn the pilots up a 1/4 turn.
If anyone in auckland knows more than me (everyone heh) could just like listen to the bike and maybe you'll know whats wrong.

paturoa
9th April 2006, 23:19
Don't be too quick to tweak the pilots, they only do from idle to about 1/8th throttle. For example it may be spot on for pilots and lean off the mains. The size of the main jet, needles and needle height all come into play above 1/8 throttle and the pilots have no effect at all above about 1/2 throttle.

A 1/4 turn is too much as well.

If your plugs are not showing lean then there are a whole bunch of things to check and tune before going there, eg how are the float levels?

Rich develops a light black soot first on the ceramic piece surrounding the post that sticks up. If it is very rich then the metal post and hood thingie go black & sooty as well and it will just keep building up.

Correct leaves it mostly clean and the creamic piece goes a tan to light tan colour. Sometimes it will just be black on one side. Thats ok.

Lean leaves white / grey deposits and no black at all.

Lean is BAD! Rich is just a pain.

Get a set of clean / new plugs and go for a restrained 5 min ride with little throttle opening. Stop and kill the motor. Burn your fingers and check the plugs. Take a piece of paper and pen with you and mark it with 6 columns. Write in the the first column what u just did, eg 5 minutes little throttle. For the next 4 write down what you see on the plugs for each. Now if you want to change anything eg one plug is darker than the rest then only change 1 pilot air screw (not the pilot) and write in the last column what you just did. eg pot 3 A/S out 1/16th.

Believe me using a sharpie to mark the original settings and writing things down may seem anal now but you will quickly see why when the tweaks you do only make things worse or no change at all.

If you are happy with the low opening then find a long piece of straight road. Have a look at the plugs first and then go for a quick ride and give it heaps, doesnt take too long. Hit the kill switch and pull in the clutch and coast to a stop with the motor off.

Do the plug thing again.

I just Googled "reading spark plugs" and there was almost 1000 hits. Have a read.

vifferman
10th April 2006, 07:17
Have you bought the balancer yet? I've got one, used three times, if you're interested I can do you a good deal.

Edit: I see you've already got it (shame).
If anyone else wants to buy a carb balancer, it's for sale. As new, comes with all the fittings and instructions, and I'll even show you how to use it. Can be used on twins, triples or fours.

Nolan
10th April 2006, 13:14
yea i posted that just before i went to get. damn is it a gauge or mercury balancer? and how much?

On another note, does anyone know where i could go to get my cbr seat re'covered? Its got a rip on it.
The cbr is starting to look a little better now. I think its had a rough life:no:

The Pastor
14th April 2006, 17:23
Have you bought the balancer yet? I've got one, used three times, if you're interested I can do you a good deal.

Edit: I see you've already got it (shame).
If anyone else wants to buy a carb balancer, it's for sale. As new, comes with all the fittings and instructions, and I'll even show you how to use it. Can be used on twins, triples or fours.


Are you in auckland? I may be keen - IF you show me how to use it :)

Motu
14th April 2006, 17:47
So I could tune my 3 bikes all at the same time! I'm not sure if I can see an advantage here,but I'm sure it's a sensable idea and I'm just too stupid to realise the benifits....

Ironman
15th April 2006, 08:11
If using a mercury balancer just remember to leave the throttle alone and raise the idle with the idle screw. A mate borrowed my balancer and blipped the throttle sucking all that lovely mercury straight into his bike.

Pixie
22nd April 2006, 00:58
If using a mercury balancer just remember to leave the throttle alone and raise the idle with the idle screw. A mate borrowed my balancer and blipped the throttle sucking all that lovely mercury straight into his bike.
That's not good!
Mercury dissolves aluminium.

Bonez
22nd April 2006, 04:26
That's not good!
Mercury dissolves aluminium.It get pretty hot in them there combustion chambers.

http://www.du.edu/~jcalvert/phys/mercury.htm

Did a similar thing with Gerty. Not the whole lot, but some. Just decided "oh well" disconnected the vacum tubes, placed the screws back in the carb manifolds and revved the hell out of the engine then went for a 300km ride. 14 years later..................http://www.kiwibiker.co.nz/forums/showthread.php?t=6072&highlight=cb750fc2

Made up a balancer using a car vaccum gauge rubber tubing and a 4 tap fitting designed for fish tanks. Already had the adapters from the mercury set.

This link may help others in there quest for balancers-

http://www.kiwibiker.co.nz/forums/showthread.php?t=23505&highlight=wet+pets

Nolan
22nd April 2006, 14:37
Ok if one header is way colder than the rest, low down power is useless(flatspot at 6500K) but high revs seems normal, apart from the cylindars make an out of balance sound?
I created the flat spot as ive balanced the carbs(gauges were are all lined up)
I think that if i pull the carbs off and visually see that they are all lined up, that one will be out?

paturoa
22nd April 2006, 19:01
- How much throttle for the flat spot? ie accel at half throttle?
- Colder at start and idling?
- Have you done a compression test?

Buy 4 new spark plugs, warm up the motor and change the plugs to the new ones. Do a LOW throttle run and look at the plugs. They should all be the same. Remember that balancing the carbs is only for small throttle openings.

This is where it gets interesting - could be a whole bunch of things. You will have to eliminate them one by one and only one at a time.

Throttle cables, different needles, main jets, needle heights. I'd check the float levels first.

MWVT
2nd May 2006, 14:36
yea i posted that just before i went to get. damn is it a gauge or mercury balancer? and how much?

On another note, does anyone know where i could go to get my cbr seat re'covered? Its got a rip on it.
The cbr is starting to look a little better now. I think its had a rough life:no:
Seat recovering. Just got my shitty old VT250 seat recovered. Rang around quite a bit got quoted 150-200 repeatedly, hit on a guy in onehunga, Marsden Auto Trimmers, did it for 70. Far as i can tell did a good job too (not that i'm any kind of upholstery expert). Put it this way, you could do worse :)