carb rebuild.

[whiteboy]

I have just bought an 87 genesis and having a running problem. In the low rev range the bike is very lumpy and does not pick up properly til about 4k. The problem seems to get better as the bike gets warm but still there at low revs. After doing a bit of research I see it could be the emulation tubes but am I rite in thinking that as mine is not an exup I don't have these? So before I rip apart the carbs for a good clean is there anything in particular I should be looking for? Also can anyone tell.me the.dry float height is it 14mm like the exup? Also can someone tell.me.stock setting.of the carbs so I least have a starting point needle position etc.

Many thanks.

[DonTZ125]

Poor running that improves as the engine warms suggests you're too lean at idle. Try setting your mixture screws.

[whiteboy]

Anyone have any ideas on a place to start with mixture screws settings? Forgot to mention it also has an occasional pop from the exhaust, would this suggest running rich?

[DonTZ125]

Typical settings for the FZRs is 3 turns out from touching down. A lean-misfire will bring unburned fuel to the hot header, resulting in a pop.

[whiteboy]

Brilliant thanks. is that 3 full 360 turns? Also any ideas on dry float height? And needle height position? Only mod is a slip on yoshi can. Am I rite in thinking I don't have the expulsion tubes?

Thanks.

[DonTZ125]

Yes, 3 full turns. Not sure on float height; according to the manual the fuel height (measured with a tube attached to drain) is 7.3-9.3mm. Needle clip is second from the top.

And you most certainly have emulsion tubes, aka nozzles aka needle jets.

[whiteboy]

Adjusted pilots and seems to be running a little better but will give them a proper strip down and going over soon. Just went for a ride and another problem that is abit worrying is under hard acceleration the bike hesitates then there feels to be almost like a bang from the rear wheel and of it goes. The chain looks to be the rite tension and nothing feels loose and doesn't feel like the clutch slipping but almost like someone has pulled the clutch in and dumped it. I can feel feel it through the pegs. Any ideas?

Thanks.

[GreyImport]

Front sprocket nut tight ? ... lock washer doing its job ?

[DonTZ125]

Sounds like the the rubber inserts for the cush drive have hardened and shrunk. The rubbers aren't terribly expensive, so - if that's what it is - replace them before you ruin your clutch, transmission, chain, sprockets, rim ...

[whiteboy]

Checked lock nut and is tight. I'm not sure if the problem could be clutch related, just went out for another ride and the best way I can.describe it is like someone pulling in and realising the clutch very quickly 3 or 4 times and then accelerates no problem. Any way I can test clutch to see if the problem lies there?

Thanks

[coops]

, just went out for another ride and the best way I can.describe it is like someone pulling in and realising the clutch very quickly 3 or 4 times and then accelerates no problem. Any way I can test clutch to see if the problem lies there?

Thanks

Exactly the same symtoms as mine had. Mine was slipping clutch. New springs and frictions sorted it. maybe just springs will do for you. Pull the clutch, measure spring length and plate thickness, warpage, basket wear. GET A SHOP MANUAL
Your carb problem...Has the bike sat unused for a while? Could be crud in the carb. Drop the bowls off and have a look. A full strip down is not usually nessasary. The problem is nearly always at fuel level where there are a few jets, while the rest of the carb is sparkly clean.
Is it a problem with one cylinder? Start the bike from cold, take the revs straight to where it runs worst, put your hand on the exhaust pipes, see which one is coolest. Pull that bowl. If its #2 cylinder it could be water in the fuel/Crud.
Be carefull, the pipes get very hot fast.

[whiteboy]

Before ripping the clutch apart I hear people use the yzf750 complete clutch with little modification. Is this worth doing or not? Which is the best manuals to get, Haynes? At there any downloads? Is tearing out the clutch a particularly big job?

Thanks

[coops]

Before ripping the clutch apart I hear people use the yzf750 complete clutch with little modification. Is this worth doing or not? Which is the best manuals to get, Haynes? At there any downloads? Is tearing out the clutch a particularly big job?

Thanks

Well yes they do yzf750 conversions. But its not just a little modification. It can be a bit tricky. Depends what you use your bike for....if its just street use, i wouldnt bother. Your basket hasnt exploded yet so no worries. Unless your going to chase more power, leave it alone. Get the yamaha workshop manual, there is a lot less mistakes in the yamy manual than haynes manual. dont know where, but im sure you can download one. Get it printed and bound. It may cost you a fitty, but it could save you 20 hunj. Clutch removal is relatively easy. But A MANUAL WILL HELP. Depends how mechanicaly minded/ experienced you are?
Welcome, and good luck. There are others here that know alot more about these bikes than i do, hopefully they will chime in if needed.

[whiteboy]

Thanks for all the advice. big thanks to GreyImport for sending me a manual. Any advise what friction plates and springs to go for?

Cheers.

[whiteboy]

Oh and sorry anyone know of best/cheapest place to source the parts in the UK?

Thanks.