GT550 vs GT750 4LS front drum

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Acebars

Re: GT550 vs GT750 drum

Post by Acebars »

canaletto5 wrote:I've been talking about the back drum !
threw a spanner in my works.. Although I note I did not say 4ls front.
ive always been of the opinion that 550 and 750 front ends are they same i havent owned a 550 J'
The 4ls drums are different, I've seen them. 550 is narrower and 750 is wider this is at the hub.

That page doesn't help. Would really appreciate some measurements!
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mark.read3
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Re: GT550 vs GT750 drum

Post by mark.read3 »

Hi Acebars, welcome to the forum. I'll make a copy of this thread and post it in the gt550 section, just in case anyone has an early 4ls gt550.
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yeadon_m
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Re: GT550 vs GT750 drum

Post by yeadon_m »

I measure 117-118mm from brake plate cover when installed in the hub, to the surface of the left side of the hub (GT550A). I don't have the sprocket carrier. I stuck a screwdriver through and marked it then measured that.

I cannot make the same measurement on the 750A as its built up and in the bike!

Anyone with a loose 750 rear drum plus brake plate for a comparison?

Mike

ps: ooops...I am on wrong track, fronts are all discs on my GTs!
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Acebars

Re: GT550 vs GT750 drum

Post by Acebars »

yeadon_m wrote:I measure 117-118mm from brake plate cover when installed in the hub, to the surface of the left side of the hub (GT550A). I don't have the sprocket carrier. I stuck a screwdriver through and marked it then measured that.

I cannot make the same measurement on the 750A as its built up and in the bike!

Anyone with a loose 750 rear drum plus brake plate for a comparison?

Mike

ps: ooops...I am on wrong track, fronts are all discs on my GTs!
Indeed I wasn't clear this is about 4ls front drums!
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heathcliffe

Re: GT550 vs GT750 4LS front drum

Post by heathcliffe »

in that case then they are ALL the same, i bought a back 550 wheel and used it on a gt 750,!
Glenn
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Acebars

Re: GT550 vs GT750 4LS front drum

Post by Acebars »

heathcliffe wrote:in that case then they are ALL the same, i bought a back 550 wheel and used it on a gt 750,!
Glenn
I have been told several times by several people who have used both that the 550 and 750 4ls front drums are not the same. The 750 is 6mm wider.
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mark.read3
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Re: GT550 vs GT750 4LS front drum

Post by mark.read3 »

heathcliffe wrote:in that case then they are ALL the same, i bought a back 550 wheel and used it on a gt 750,!
Glenn
Dude, you need to stay off the medication.
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Alan H
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Re: GT550 vs GT750 4LS front drum

Post by Alan H »

Me three.
The front drums are the same.
I really must start to take more notice of what's posted..................
Proof that four strokes are over complicated
barney01
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Re: GT550 vs GT750 4LS front drum

Post by barney01 »

Hi I have a 550 J with a 4LS if you want any measurements let me know.
NO SMOKE .......NO POKE
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Alan H
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Re: GT550 vs GT750 4LS front drum

Post by Alan H »

Well. Looking HERE and on HERE and comparing the parts numbers with those in my original 550J parts book, the hubs are different part numbers, but just about everything else is the same. Brake plates, shoes, fittings, spacers etc. etc. I don't know what the difference in the hubs might be, but can't be a deal as the triple tree base is the same part number for 550 and 750 J models. The triple tree top is different, and the springs and dampers are different, otherwise it would seem that they are as near as dammit the same.
Proof that four strokes are over complicated
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