My GK76a winter service/tidy-up project.

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morris147
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Re: My GK76a winter service/tidy-up project.

Post by morris147 » Wed Jan 20, 2016 12:42 pm

Sorry to hijack Wullie, where did you get the needles and needle jets from?

wullie3xv9
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Re: My GK76a winter service/tidy-up project.

Post by wullie3xv9 » Wed Jan 20, 2016 1:30 pm

Hi Morris, no problem. The new OEM needle's were sourced via my local Suzuki dealer & the OEM O-5 needle jets were sourced from NRP Carb's in Manchester, U.K. You may get both from NRP but that's who I got my new parts from.
Hope this helps. ;)

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Re: My GK76a winter service/tidy-up project.

Post by Variablevalves suck » Wed Jan 20, 2016 10:47 pm

NRP have needles listed on the website.

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Re: My GK76a winter service/tidy-up project.

Post by 4hundread » Thu Jan 21, 2016 10:06 am

Hi Wullie, not going to let my impatience get the better of me this time! In fairness, the bike was frustrating at times but no more than my SRAD was and it never broke down out on the road. Did a lot of miles on it too.

Give me a pm or a text regards the disc, will be in Kirkcaldy next weekend at the powder coaters so could swing by. Cheers mate.

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Re: My GK76a winter service/tidy-up project.

Post by Hubbskiboy » Tue Feb 02, 2016 9:03 pm

Hi Mate.
Did your carbs not have a return spring on the plastic choke cable slide?
Mine did originally, but I've lost the darn thing and I can't remember how it was fitted!
All the pictures of carbs I can find online don't have a spring which makes me think either it was a bodged add on to get the slide to return promptly or everyone else has lost their spring too!
It was only a flimsy thing but it's bugging me now.
Ta.

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Re: My GK76a winter service/tidy-up project.

Post by wullie3xv9 » Wed Feb 03, 2016 2:55 pm

Having just looked at the GK76 Mikuni Carb's parts manual elsewhere in 'ere it doesn't look like a spring was fitted there as standard. There should be a return spring on each of the four brass choke valves, but they're hidden behind each of the choke valve seals, so it looks like your single spring at the plastic choke cable connector slide was an ... ehm ... extra.

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Re: My GK76a winter service/tidy-up project.

Post by Hubbskiboy » Wed Feb 10, 2016 5:19 pm

I reckon you're right about the 'extra' spring.
I suspect that the side wasn't returning as well as it should because it's so corroded and filthy, so the genius previous owner decided to add another spring.
Although the plastic choke cable slide actually does have a hole it would seem to attach a return spring?
Can you give me some of your expert advice on how well the plastic slide moves up and down the aluminium cylinder?
Mine is loose as hell the the point where the play is at least a couple of mm up and down.
I've ordered another one from the Suzuki Parts website, just to be safe.

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Re: My GK76a winter service/tidy-up project.

Post by wullie3xv9 » Fri Feb 12, 2016 11:58 am

The plastic choke slider on mine's on the loose side too ... but if I close the chokes with the bar lever they do all shut off as they should. When you fit the new slider you could always smooth off & polish the alloy tube it slides on & then lube it regularly with GT85 / WD40 type stuff. ;) Not grease though as that'll just turn into a grinding paste! :roll:
Might also be a good idea to check if any of your 4 brass choke valves look bent. The No. 1 cyl's carb brass choke valve on mine was found to be bent when I dismantled the carb's to fit new seals ! :roll:

Did you find the couple of photo's in here of me doing my engine's valve clearances ??

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Re: My GK76a winter service/tidy-up project.

Post by Hubbskiboy » Sun Feb 21, 2016 8:22 pm

Hi Wullie.
Blimey, you're a mind reader. Yes the choke valve on the 1st carburettor (far right) was bent as hell!
I thought I'd damaged it myself when I tried to pull it out without removing the plastic retaining clip first. :oops:
I knew it was bent because when it twisted it with my fingers it wasn't smooth at all.
All the other 3 were OK though.
Anyway I ordered a new one from bike-parts-suz.com and it's arrived already.
It looks like I'm going to have to bite the bullet and take the engine out of the bike for a top end rebuild. :(
Got any tips on how to do this? I may have to do it on my own. Is this possible?
Also, how did you clean your engine down? You didn't say whether you just scrubbed it yourself with brushes etc or if you got it steam cleaned.
I've just thought of something else I need to ask you.
Are you aware of any good bike mechainics who have experience working on these kind of engines?
I found one bloke who I've been in regular contact with who seems to know what he's talking about.
His name is James Wright-Roberts (Jim) and his business is called 'The Superbike Surgery Ltd'.
Ever heard of him?

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Re: My GK76a winter service/tidy-up project.

Post by Variablevalves suck » Mon Feb 22, 2016 8:39 am

you can get the engine out yourself, not too bad.
helps if you can get the use of a trolley jack to take the weight while you do the spanner work.

If you are after someone to rebuild the top end then Mike at BMC (Whitchurch) or Kev at Projex (Cradley Heath) both know their way around a 400 motor.


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