GT550 - Surging off throttle - educate me on carb removal

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TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

:mrgreen: Ok fine, the regulator has been regulated!

In other good news, I re-checked the manual again and the rear brake has tons of wear left (front as well). I was backwards on the wear indicator marking. However, anything I can do about the front disc squeaking? :wth:
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Alan H
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by Alan H »

Don't oil it!
We jokingly told someone to do that to his CB750 disc many years ago and he started complaining that his front brake was less effective......

The probable cause is glazed pads and/or glazed disc.
Change the pads, they may also have other stuff on them that shouldn't be there and you don't know how old they are - or if there is much pad actually left - it may be the pad backing that's touching the disc when you brake.
You can VERY LIGHTLY with VERY FINE emery paper, rub both sides of the disc (while spinning the wheel) and that will deglaze it.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

Ha! Well, hope he used a good quality oil on it. Wonder if it stopped squeaking? :P

I can clearly see the red wear indicator mark on the pad with lots to go so unfortunate to change them but yeah, probably glazed and in need of fresh ones. It's not horrible and not consistent but when it does let out a squawk it sounds like a wounded eagle! There's no scratching on the disc whatsoever as if something terrible is starting to happen so sounds like a good one to put on the rainy day projects list. I'm in Seattle so we get plenty of those...
TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

OK, looked again and I lied. ONE of the pads has plenty of meat left. The other, not so much. I looked through some manuals but the owners manual says to take it into a shop if the pads are due and the Clymer manual goes into a complete breakdown of the caliper. What do I really need to know to replace the pads? Will I need to bleed it or can I simply remove the caliper, replace the pads, and slide it back over the disc?

Thanks again!
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Alan H
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by Alan H »

TRC wrote:OK, looked again and I lied. ONE of the pads has plenty of meat left. The other, not so much. I looked through some manuals but the owners manual says to take it into a shop if the pads are due and the Clymer manual goes into a complete breakdown of the caliper. What do I really need to know to replace the pads? Think first
Will I need to bleed it or can I simply remove the caliper, replace the pads, and slide it back over the disc? Yes

Thanks again!
Caliper off (or wheel out) then a screwdriver or similar between the pads and lever them apart SLOWLY - make sure the brake fluid doesn't overflow the master cylinder or it'll bugger up the paintwork underneath.
Change the pads, and put the caliper back on/wheel in BEFORE you squeeze the brake.
NOW squeeze the brake and it should work OK. If you moved the calipers way back, you may have to pump the brake at first. Check brake fluid level.
Any doubt, buy the pads and let the local bike shop do it.

I thought I had a brake manual on disc, but I can't find it. Bummer!
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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ConnerVT
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by ConnerVT »

TRC wrote: However, anything I can do about the front disc squeaking? :wth:
Get a cat.
TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

ConnerVT wrote:
TRC wrote: However, anything I can do about the front disc squeaking? :wth:
Get a cat.
Yep, my dog is good-for-nothin'.
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

Alan H wrote: Caliper off (or wheel out) then a screwdriver or similar between the pads and lever them apart SLOWLY - make sure the brake fluid doesn't overflow the master cylinder or it'll bugger up the paintwork underneath.
Change the pads, and put the caliper back on/wheel in BEFORE you squeeze the brake.
NOW squeeze the brake and it should work OK. If you moved the calipers way back, you may have to pump the brake at first. Check brake fluid level.
Any doubt, buy the pads and let the local bike shop do it.

I thought I had a brake manual on disc, but I can't find it. Bummer!
Excellent, thanks - I ordered the pads (EBC FA55). I've done it on my KTM 380 EXC and the procedure sounds about exactly the same so I think I'll give it a go.
GTandcbr
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by GTandcbr »

Just one observation. Why has one pad worn down more than the other? Maybe a piston sticking in the caliper? Just saying....
98 carb Blackbird and GT550j
TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

It's definitely weird. One side is highly worn, the other much less so. The red marking is about dead center on the less worn side, totally gone on the worn side. Ok, so let's say it is stuck which seems likely, how to un-stuck it??
GTandcbr
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by GTandcbr »

Strip the caliper down and good clean. You can get a service kit http://www.ebay.co.uk/itm/Suzuki-GT-550 ... SweuxWQxxl" onclick="window.open(this.href);return false;
98 carb Blackbird and GT550j
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by yeadon_m »

The squealing can be because the calliper isn't sliding freely on its two allen headed bolts and cocking slightly on application. Check they are free and you can move it by hand easily with the wheel out. Or, the piston side pad is vibrating on the piston. Put a little copper grease on the back of the pad. DON'T let it onto the sides of the pad. Or just the pads are glazed. If not too worn (sounds like one might be) you can give it a few rubs on 120 grade paper on a flat surface to de-glaze their faces. Or the disc is dirty per Alan's advice. Clean the disc with carb cleaner on paper towel afterwards.
My GT750A brakes sounded like they had a few tortured rodents in for a few miles after rebuild with all new or restored parts. The copper grease and/or a few more miles made them bugger off. Sounds like they came to you :-)
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TRC
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by TRC »

Stripping and rebuilding sounds like a good idea. Might as well do this right as it's suspect to begin with and well, I like my motorcycle brakes to work properly.

What do you guys think of this rebuild kit instead? A bit more money than the Powerhouse kit but is OEM parts, has a new piston, and I could actually go pick it up instead of it being shipped half way across the world: http://r.ebay.com/1I7y4Y" onclick="window.open(this.href);return false;
GTandcbr
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by GTandcbr »

No brained for me. If your bike is a keeper fit the best. As you quite rightly say brakes are important to me too!
98 carb Blackbird and GT550j
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Alan H
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Re: GT550 - Surging off throttle - educate me on carb remova

Post by Alan H »

B8ES, A and onwards according to the manual.
Mind you, we tend to ride harder in the UK. :roll:
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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