(GK7AA) Front Brake Disc and special tools

[tomx611]

I found my b4 valve sound is too loud, i want adjust the valve but the manual said i need a special tool, and the special tool seems difficult to find. did any tool can replace the special tool?

my front brake disc also get loose on the outside disc, the pins were get rush. can a honda cb400vs brake disc fit on the gk7aa B4, or other can replace it?
coz cb400vs is popular in after market.

thanks!

[Chris H]

Hi Tom,
You can simply use a long bolt. I use the pin that holds the right hand switch gear on and put it through a 30mm peice of plastic cut from a cheap pen and then just screw it in till it pinches up tight. It only has to allow you to turn the follower shaft left and right.

Regards the disc it is the same as the earlier twin disc bandit4, gk74A gsxr4, early RGV250 and early SV650.
Hope this helps Chris.

[tomx611]

Thanks Chris!

Did it's easy to adjust the valve on a gk7aa bandit, this is my first time to open the engine cover, and which place should pay attend on?


tom

[Chris H]

The gk7AA has a VVC inlet cam and a normal exhaust cam. The exhaust is a simple job of undoing the lock nut and adjusting the pin to give the correct valve clearance, but the inlet is very complicated so give the manual a VERY good read before starting the adjustment. By turning the special tool to either the left or right you will move the cam follower to bring either the low or high speed cam into use and so have to adjust the correct shim at each setting. IMPORTANT- you can adjust either shim with the follower in any position and so it is very easy to set the wrong jap for the wrong setting, after setting high/low setting you then set the play between the high/low components using the nut and pin as per the exhaust and this also needs the follower in the correct position. It is apain in the head to do and its very easy to drop shims down inside the motor so get two magnetic pick up tools to allow you to remove one shim and then replace with another.
Chris.

[tomx611]

thx!

Let me try later.

[tomx611]

Chris

i have taken away the engine cover, measured inlet hi and lo clearance, and it's easy to replace the shims. the difficult part is the adjustment of the sub rocket arm play, it seems need the suzuki tool to adjust, did there any method other than use the suzuki tool?

[Chris H]

You can buy the tappet adjusters cheap from tool shops. I just use a T bar socket and do it the slow way by unlocking the nut and then adjusting the pin, takes a couple of goes but its so tight in there with all the VVC stuff that it worked out be the simplest way. Its so tight that i had to grind down the edge of the T bar to get the socket to fit the nut correctly.

A picture of the top end showing a tappet tool, it was so tight i went with the other method.

Chris.

[tomx611]

Cool, Chris! you are great.

i just finished
adjusted the exhaust pins within 0.20-0.25,
replaced some lo side shims near 0.13 ,
but not stocks for the hi side shims,
no sub rocker arm play adjustment,

and the engine idle still too noise. do u know where's the problem?


Can u take a seperate photo of the tools? and i can easy to buy the tools.

to loosing the nuts, i know it's 8mm
and how about the adjust the pin?

Thanks

Tom

[Chris H]

Hi Tom,
below is a link to a tappet set, they are a wast of money as they are TOO wide and not long enough, i machined and extended mine and it still wouldnt work.
http://www.mandp.co.uk/productinfo/500607/Workshop/Tools/Motion-Pro/Tappet-Adjusting-Set

best thing to do is just get a T bar and make something that can turn the squre.
http://www.mandp.co.uk/productinfo/500607/Workshop/Tools/Motion-Pro/Tappet-Adjusting-Set
 I used one of these that was ground down at the end, slow but cheap.
Hope you got the gaps correct, 0.20/25 at the exhaust and about 0.15 for the inlet for high/low and rocker play. Did you have the cam in the correct place for each setting? ive rebuilt a complete engine quicker than adjust one of these VVC motors and think it is just about the biggest hole in the head ive every had with a bike. Your lucky as you got a 75AA thats only got VC on the inlet, ive got the 75A VM with VC on the exhaust as well!
If the valves are close and the motor is still noisy you could check that the cam chain tensioner is working correctly, also the oil pressure.
Chris.

[tomx611]

Chris

i adjusted the valve finially, although i make the diameter of the 8mm T bar smaller, i also can't fix the center screw, they move togeter when i tight the outer screw........ at last, i take away the intake cam shaft to adjust, and i get the good valve clearance.

i also replaced a better carburetor, the better carb was placed for half year not use. and i start the engine, only the 2nd cylinder can fired.... the other seems flooding of fuel.

i 'm so worry the flooding will case the spark plug damage...,
and did you know what's the factory setting of the idle screw?

Thanks!

Tom

[Chris H]

Hi tom,
Good work
The idle screws are 1.5 turns out.
There are workshop manuals in the download section.

[tomx611]

i make a serious mistake.........

i exchanged the 3rd and 4th plug wire, it works fine now, but still noisey.........

thx chris

[Chris H]

Good work tom,
If its still noisy i'd be inclined to take another look- i Know them valves are a pain in the ass to do! took me longer to do the valves than rebuild the whole motor.

[pmackie]

Any chance that you are hearing cam chain noise...the tensioners are know to have some issues.

[tomx611]

i took the tensioner from the engine, i can use a screw driver to shortern it smoothly, did it get chance for the cam chain too lossey.......... it's seems very trouble if the problem from the chain.