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Carb jets

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Graeme77:
Sorry, more questions from the newbie ::)

Decided to take my carbs apart. They have obviously been apart before, and i suspected they were all over the place.

I was right  ;D

Cleaned everything out and no blockages. One float valve was a little sticky, but i had a new spare.

The top grommet seals in the top caps weret seated right which im sure was slightly effecting the way they shut. All sorted now though.
Float levels were all over the place, but all correct now.

The last thing, and the thing im asking about, is the needle jets.

The actual needle jets were located on the 5th? setting, holding the needle up highest. Ive put them onto the middle ring, as standard, but im not sure if the 5th ring placement was intentional.
I have 132.5 jets in it.
These will richen it up right, and lifting the needles as i have will richen it more wont it.
Any thoughts?


((((EDIT to say, by moving the needle to the middle setting ive actualy lowered the needle, that'l lean it a little wont it, not richen it.))))

Secondly, the jets themselves. 132.5, as i say, apart from one, which is 152.5!!!

I have a spare set of incomplete carbs. These have a set of 116 jets in. Should i use these, get another 132.5, or something else?

The bike has pod filters (i have the origional air box though) and an aftermarket 4-1.

The last thing is the jet holders, the tubes with all the little holes..The ones on the bike, with the 132.5 jets, have very small holes for the first 2, the other 3 are slightly larger. On the holders with the 116 jets, these first 2 holes are pretty much the same size as the other 3.
Whats the difference with these?

Oh, i forgot, one other thing too.
There are little tubes linking the carbs together (not the fuel tubes). Carbs 1/2 are joined and carbs 3/4 are joined. However, where the throttle return spring is the pipes are open. Should these also have a loop of tube joining them?

Thanks, ill get this think purring eventualy :)

Graeme77:
I fitted the tubes with the bigger holes and the 116 jets, synced them on the bench, ill see how it runs now.

It was rich before, and idled rough (no wonder with 1 huge jet!).

Not ridden it yet though, so untill i get some vac gauges and can take it for a spin there's not much else i can do.

Graeme77:
It runs better now. Picks up real quick when you blip the throttle. Sounds better but isnt too smooth idling at 1000rpm.

Primary chain rattle was a bit better too.
Re-fitted the stock air box and got a big improvement. Idle at 1200 and any revs above that and the primary rattle is all but gone. Trying to let it idle at 1000rpm and its lumpy. The primary chain rattles on every lump as the crank tugs on the chain.

So, heading in the right direction, not a bad result i guess for a bench sync.

Time for some gauges, maybe ill flog a few spares on ebay to fund them.

Bike seems to be slowly going back to stock LOL.

K2-K6:
Ha, no wonder it was chuntering it's chains with carb set-up like that. Seems you're getting it to how it should  be though now.

Mostly it's hard to get a really even tickover below about 1100rpm, perhaps when brand new maybe a little lower but I percieve it to be kinder to the generla health of the chains to be smooth at that rather than chase a lowered figure without any good reason.

As you've found you can get the sync pretty close by eye when on the bench but you can also do them with an improvised "feeler gauge" under the slide to get a really good physical match and I'd be willing to bet they'd be very close when checked with vac gauges.

Graeme77:
I set them using a piece of mig wire as a feeler gauge, from the head side of the carbs.

I guess i now know why the exhausts all blued at a different rate!

Going to look at ignition again tomorrow, i timed it static, then checked with a ligth, but it was bouncing around at idle. Ill see if i cant settle it down a little.

If not ill just let it idle high.

My old 125, with a micron, made no power untill 3500rpm so i set the idle at 3250rpm ;D

Only for a day of so, screaming at the lights got tiresome.

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