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Carb sync 3HE


steve_w
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Hi people, hoping someone can help.

I've got a 91 J reg FZR 600 3HE.

I've borrowed a dial type gauge off a friend from work and bought the 6mm adapters from morgan's web site.

I've hooked it all up and started to adjust the 3 screws, 1 & 2, 3 & 4 and 2 & 3.

I can get 1 & 4 in the normal scale on the dials but 2 & 3 won't go anywhere near. However, 2 & 3 are in the late valve timing or leak at intake manifold or heat riser portion of the dials. Little bit above my head at the moment.

Idle is around 4k and i can't back it off.

Now then, this is the first time i've attempted this so probably not doing it right. I take it you adjust the carbs with the 3 screws that you can see by looking in between the carbs?

Really don't fancy going to work on the mountain bike tomorrow :o(

Any help will be really appreciated.

Thanks, Steve

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Managed to get them all fairly equal with a normal tickover. gonna give it some investigation when the manual i ordered on thursday arrives. at least it seems to be as it was before (lumpy idle)

It's a bit of a learning curve this bike business isn't it :blink:

In the meantime, if anyone can offer some tips it'd be a real help

Thanks

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Managed to get them all fairly equal with a normal tickover. gonna give it some investigation when the manual i ordered on thursday arrives. at least it seems to be as it was before (lumpy idle)

It's a bit of a learning curve this bike business isn't it :blink:

In the meantime, if anyone can offer some tips it'd be a real help

Thanks

I havent done it on an FZR but my old suzuki had to be balanced at 2500rpm or you were setting it to the idle jet rather than the diaphrams and it made no difference Till you went down the road.

If you are having trouble getting the revs to hold i would check to be sure the adjusters are working and that there are actually no leaks/bad plugs or way out valve clearances first before the carb balance, unless you want to tune your engine around a fault.

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Cheers. Like I said, I'm gonna wait for the manual to arrive and then do some digging around.

It's a 19 yr old bike with 8 previous owners, some of which have had some interesting ideas about maintaining it from the look of things so I'm ready for a bit of work. Obviously helps when you have a better idea of what you're doing! My last bike was a TZR 125 20 yrs ago so I'm a bit 'green' with this :P

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Cheers. Like I said, I'm gonna wait for the manual to arrive and then do some digging around.

It's a 19 yr old bike with 8 previous owners, some of which have had some interesting ideas about maintaining it from the look of things so I'm ready for a bit of work. Obviously helps when you have a better idea of what you're doing! My last bike was a TZR 125 20 yrs ago so I'm a bit 'green' with this :P

One thing i would do much as it will sound silly at first. CHECK THE HOSES ON THE GAGUES i repeat CHECK THE HOSES ON THE GAGUES. I dont mean to be patronising but i know it can affect things badly. (Don't ask)

Secondly Set the revs to whatever its ment to be for a carb balance, then get each gague and see what it reads on one particular cyl. And check how it reads whatever it may be on that cyl. Then when you are adjusting the cylinders you know the gagues are singing from the same book.

Finally if you have a cyl reading really low dont assume the engine is dead with ignition and all that other faf. Job no1 check the diapram in that carb. ;)

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Funny you should say that Cynic.

The adapters I bought from Morgan came with little nitrile 'o' rings on them. Looking at how they were seated made me take them back out and use the brass washers that are on the screws instead. That allowed me to at least get the cylinders pretty much equal and brought the idle back down to normal. At one point one of the hoses split where it goes onto the gauge.

To be honest, the bike runs well on the road (can be a little lumpy below 3k) but the idle sounds rough. I can't tell you what it's ticking over at exactly as the rev counter bounces between 1 & 2k although it's fine when actually riding (could be a symptom of something else, could be a dodgy rev counter)

Anyway, my manual should be here tomorrow so I can start to get my head round it.

I'll post any findings on here, hopefully there won't be too many problems B)

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