Gearbox woes

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Rustyp81
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Bike owned: Cagiva Mito. VFR400R NC30
Location: Worcester

Re: Gearbox woes

Post by Rustyp81 » Fri Aug 27, 2010 12:54 pm

Hello,

Checked all the plates. I now have 10 3.06mm fritction plates and 9 steel plates. The clutch is noicably better. No slip when pulling away, much better lowend grunt but still the problems up the top end.

All the reading i have done sugestest replacing the springs if the clutch is slipping but the vfr seams to have diffrent springs to most other bikes or am i just getting confused and is it worth replacing them??

The other thing that keeps cropping up is using proper oil , as in proper bike oil that has anti slip stuff and is desgined to work with a wet clutch, unlike car oil, which i didn't know. I have yammalube in there at the min so unsure if changing it will help? What oil do you chaps recomend??

I'm pretty convince it's the clutch slliping as it apears to be happening when the engine hits higest tourqe which again, only from what i have read, is the prime time for a clutch to slip. Just thought i would ask you guys for your opnion as everything i have read so far is just genral bike info rather than VFR specific.

I also think she's running a little ritch now as when stoped at lights you get a strong smell of burnt fuel but i guess it's best to sort this problem out first?

Cheers

Russ :grin:

ozracer
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Re: Gearbox woes

Post by ozracer » Fri Aug 27, 2010 1:06 pm

My race bike has an extra clutch spring and it really makes it bite a lot harder. A little stiffer to pull the clutch lever in, but I can live with that. :grin:

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superlite
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Re: Gearbox woes

Post by superlite » Fri Aug 27, 2010 1:09 pm

ozracer wrote:My race bike has an extra clutch spring and it really makes it bite a lot harder. A little stiffer to pull the clutch lever in, but I can live with that. :grin:
:plus: It's the goods!
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CMSMJ1
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Re: Gearbox woes

Post by CMSMJ1 » Fri Aug 27, 2010 1:11 pm

superlite wrote:
ozracer wrote:My race bike has an extra clutch spring and it really makes it bite a lot harder. A little stiffer to pull the clutch lever in, but I can live with that. :grin:
:plus: It's the goods!

Aye - my race and road bikes all have extra springs...

I have a grip like a python!
IMPERATOR REX ANGLORUM

The V4 is the law..

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Rustyp81
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Re: Gearbox woes

Post by Rustyp81 » Fri Aug 27, 2010 1:28 pm

so whack in an extra spring so i have four??

Any advice for oil as i may as well replace that also, just incase??

Neosophist
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Re: Gearbox woes

Post by Neosophist » Fri Aug 27, 2010 1:40 pm

As long as you have motorcyle oil in there it should be fine.

Its fully synth (and some part synth) car oils that have friction modifiers in there to imporove gas mileage.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

Rustyp81
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Re: Gearbox woes

Post by Rustyp81 » Mon Aug 30, 2010 12:07 pm

woot, bit of an update.

Put an extra spring in the clutch and replaced the cable. I can now accelerate, hard, at full throttle until around 10k then it bogs down till around 12k at which point the engine splutters and the rev needle bounces between 9k and 12k.

At a guess I'm guessing it's running rich as i have 120 mains all round in the carbs.

Reckon it's this or could it be something else?

Having the forth spring certainly makes your left hand work harder :(

Cheers

Russ
:rocks:

Rustyp81
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Bike owned: Cagiva Mito. VFR400R NC30
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Re: Gearbox woes

Post by Rustyp81 » Tue Aug 31, 2010 9:53 am

Right,

Change the jet's to 180/120 and now it pulls really hard at full throttle (The "ooops i better hold on" feeling has come back) to 10k and the the power seems to drop off, if i kick up a gear the power comes back till around 10k. The bike doesn't splutter, cough or nout but it's just like it struggling to accelerate past 10k.

So far i have

- Changed friction plates
- Changed and added an extra clutch spring/s
- Changed spark plugs
- Changed clutch cable
- Tried 4 different jet combos 115/118 - 118/118 - 118/120 - 120/120
- Cleaned and balanced carbs
- replaced vacuum hose

I have noticed that when i take the tank off, unless the fuel tap is set to off it will piss petrol all over the place is this normal being that the carbs are vacuum feed and all?

Not really sure what to tried next, any ideas??

Cheers

Russ

Neosophist
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Re: Gearbox woes

Post by Neosophist » Tue Aug 31, 2010 10:52 am

Sounds like the fuel tap has been modified.

you can remove the vaccumn hose and blank it off at the engine end if so.

Either that or you have a busted tap..

Maybe it's running out of fuel
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

Rustyp81
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Bike owned: Cagiva Mito. VFR400R NC30
Location: Worcester

Re: Gearbox woes

Post by Rustyp81 » Tue Aug 31, 2010 1:34 pm

Neosophist wrote:Sounds like the fuel tap has been modified.

you can remove the vaccumn hose and blank it off at the engine end if so.

Either that or you have a busted tap..

Maybe it's running out of fuel
She has a full tank of juice. I'll try blocking of the spigot with some silicone and if she cuts out i guess the tap is OK. Would a knackered tap cause these high end problems though??

cheers

Russ

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