GT 500: Seized screws of clutch side cover
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- Suzuki 2-Strokes: GT100, GT500
GT 500: Seized screws of clutch side cover
75 GT500:
- Do not know when was last time clutch cover screws were opened.
- Could be unopened since decades/or two.
- There are marks of attempts to open, since the screws look like almost on the verge of stripped.
- I do not own impact wrench ( thinking of renting or buying cheap/electric used one )
- Will electric impact wrench have enough power to open screws? or only high powered air impact wrench is needed.
- I do not have any experience with impact wrenches, so not sure about its potential and applicability in my situation.
- Is there any other method that I should be trying?
What are my options at this point?
Thanks in advance!
- Do not know when was last time clutch cover screws were opened.
- Could be unopened since decades/or two.
- There are marks of attempts to open, since the screws look like almost on the verge of stripped.
- I do not own impact wrench ( thinking of renting or buying cheap/electric used one )
- Will electric impact wrench have enough power to open screws? or only high powered air impact wrench is needed.
- I do not have any experience with impact wrenches, so not sure about its potential and applicability in my situation.
- Is there any other method that I should be trying?
What are my options at this point?
Thanks in advance!
- Flywheel
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Re: GT 500: Seized screws of clutch side cover
I've never used an electric/pneumatic impact on these screws. I used a hand impact driver. Pick the correct size bit, and hit the back of the driver with a hammer. Easy-peasy.
https://www.amazon.com/ARES-70006-Rever ... act+driver" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
https://www.amazon.com/ARES-70006-Rever ... act+driver" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
- jabcb
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Re: GT 500: Seized screws of clutch side cover
Buggered up screws is pretty common. The screws on vintage Japanese bikes are JIS, which looks similar but is different to phillips. A phillips screwdriver works adequately for JIS screws that aren’t in very tight, but it will bugger up tight JIS screws like those on your engine covers.
You should get JIS screwdrivers so that you don’t have this problem in the future. I use Vessel screwdrivers, which is a Japanese brand of pro quality JIS screwdrivers. But there are cheaper alternatives.
If your case screws are not too badly buggered up, you may be able to get them out with a Vessel Impacta screwdriver. You hit the end of the screwdriver with a hammer, which forces it into the screw while turning it slightly.
There are also impact drivers with bits that look like this that may work:

You can use a drill to remove the heads of really badly buggered up screws. Once the cover is off, you can use pliers to remove what is left of the screw.
You should replace any of the damaged screws. You can get a complete set of replacement screws here: http://www.rimfire-eng.com/suzukistore.htm
Plated mild steel screws are the same as original. If you decide to upgrade to stainless steel screws, then make sure to use anti-seize.
The little dimple in the head of the new screws identifies them as JIS.
Some people prefer to upgrade to stainless allen screws. Kits are available, just make sure to use anti-seize.
You should get JIS screwdrivers so that you don’t have this problem in the future. I use Vessel screwdrivers, which is a Japanese brand of pro quality JIS screwdrivers. But there are cheaper alternatives.
If your case screws are not too badly buggered up, you may be able to get them out with a Vessel Impacta screwdriver. You hit the end of the screwdriver with a hammer, which forces it into the screw while turning it slightly.
There are also impact drivers with bits that look like this that may work:

You can use a drill to remove the heads of really badly buggered up screws. Once the cover is off, you can use pliers to remove what is left of the screw.
You should replace any of the damaged screws. You can get a complete set of replacement screws here: http://www.rimfire-eng.com/suzukistore.htm
Plated mild steel screws are the same as original. If you decide to upgrade to stainless steel screws, then make sure to use anti-seize.
The little dimple in the head of the new screws identifies them as JIS.
Some people prefer to upgrade to stainless allen screws. Kits are available, just make sure to use anti-seize.
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Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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Re: GT 500: Seized screws of clutch side cover
I've pulled apart a lot of motors over 40 years, and can't remember not being able to get a screw out with a hand held impact driver and a club hammer.
Keeping old 2 strokes alive !
- johnakay
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Re: GT 500: Seized screws of clutch side cover
if your unsure still ,you can always try these.
https://www.ebay.co.uk/sch/i.html?_odkw ... r&_sacat=0" onclick="window.open(this.href);return false;
https://www.ebay.co.uk/sch/i.html?_odkw ... r&_sacat=0" onclick="window.open(this.href);return false;
If I wanted to make a life-long career out of
working with the mentally retarded I would
have opened a Harley Davidson Dealership
working with the mentally retarded I would
have opened a Harley Davidson Dealership
- johnu
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Re: GT 500: Seized screws of clutch side cover
You won't need stud extractors, either use the impact driver others have mentioned above or drill the screw head off then remove the stud that is left with mole grips when the case is off.johnakay wrote:if your unsure still ,you can always try these.
https://www.ebay.co.uk/sch/i.html?_odkw ... r&_sacat=0" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
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Re: GT 500: Seized screws of clutch side cover
another trick is to shock the screws. you need a long screwdriver bit, put it on the screw and hit it HARD with a heavy hammer. this sometimes does the trick, but as titan performance says, i'm the same, i've never failed to get a screw out with an impact driver. mine was about £5 and works perfectly. if the heads of your screws are knackered, then using the blunt bit [in the impact kit] is your best bet. i replace all my cover screws with stainless allen bolts, they are far better and easy to get out - but as has been said before - make sure you put a smear of copper grease on each one WITHOUT FAIL. you'll find having an impact driver in your toolbox is one of the best things you'll ever buy. oh yes, inside the casing there are more jis screws, that might not be buggered, so make sure you've got a couple of jis bits too
cheers, dd.

cheers, dd.
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GT250 big bang road registered. Both pistons fire the same time. USD forks.
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Re: GT 500: Seized screws of clutch side cover
One last comment.. you can make a passable JIS bit by filing the tip off a Phillips (PH) bit flat so that it sits better in the screw head..
- johnakay
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Re: GT 500: Seized screws of clutch side cover
someone on FaceBook had use this and found them ok.
so I bought 2.
(( Further to my comment yesterday ref exhaust to down pipe sea l I have searched my spares and have found seal box and seal and checked number on it it is a Payen nb 628 it is a crank/flywheel seal so withstands the heat and at present they are on Ebay for £10.57 but are black not blue but hey dam sight cheaper hope this helps everybody))
https://www.ebay.co.uk/sch/i.html?_from ... 1&_sacat=0" onclick="window.open(this.href);return false;
so I bought 2.
(( Further to my comment yesterday ref exhaust to down pipe sea l I have searched my spares and have found seal box and seal and checked number on it it is a Payen nb 628 it is a crank/flywheel seal so withstands the heat and at present they are on Ebay for £10.57 but are black not blue but hey dam sight cheaper hope this helps everybody))
https://www.ebay.co.uk/sch/i.html?_from ... 1&_sacat=0" onclick="window.open(this.href);return false;
If I wanted to make a life-long career out of
working with the mentally retarded I would
have opened a Harley Davidson Dealership
working with the mentally retarded I would
have opened a Harley Davidson Dealership
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Re: GT 500: Seized screws of clutch side cover
A great idea, but if you haven't used them before, it is worth noting that they should only be tightened using a screwdriver, NOT a ratchet, t-bar or long side of an allen key. The casing threads are easily stripped if the wrong tool is used.dollydog wrote: i replace all my cover screws with stainless allen bolts, they are far better and easy to get out - but as has been said before - make sure you put a smear of copper grease on each one WITHOUT FAIL.