gt550 fork tubes

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stlrocker
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gt550 fork tubes

Post by stlrocker »

i need to know if the fork tubes for a 550 are the same for all years, or if they changed along the lines somewhere. i have a 72 that i need to replace the tubes on. i know the lowers changed, but i am hoping they kept the same tubes. it seem like it may be hard to find a set without rust on them.
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Jughead
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Re: gt550 fork tubes

Post by Jughead »

try http://www.frankmain.qpg.com/ for new reproduction tubes.
Hang me from the Tree of Shame.Damn! I forgot the Rope.
stlrocker
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Re: gt550 fork tubes

Post by stlrocker »

yeah, i know about franks. it seems i heard they have gone up a bit since i last got some tubes from them. i havent contacted them yet, but heard that tubes were close to 300 with shipping these days. thats a good amount more than i remember, and more than i really want to spend if i can avoid it. if other year tubes fit, it will really give me a lot better chance of finding a decent pair.
Buffalo-guy
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Re: gt550 fork tubes

Post by Buffalo-guy »

As far as I know, the 550 and the 750 in 1972, used the same front end to accommodate the 4LS brake. On E-bay, check out "cruisinimage" out of Japan, as they have replacement tubes for those forks, for $80 a set. That is good value in anyone's book. I've bought a set, and so has Mr. oldjapanesebikes, and they are the real deal. The later forks are totally different internals, so will not inter-mix. The early forks have a slipper ring at the top of the leg, and a piston at the bottom of the tube. The later ones have neither, with total tube contact in the leg. Hope this helps. Cheers.
Fred
PS. The new tubes are hard chromed all the way to the top, so the old problem with corrosion under the headlight ears should be eliminated.
Suzuki GT 750s
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oldjapanesebikes
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Re: gt550 fork tubes

Post by oldjapanesebikes »

According to the Zedder index, the front fork inner tubes were not the same for the GT550 and the GT750 - 51111-34030 and 51111-31030 respectively :( Not sure what the difference is - they are both 35 mm (I posted a link to a handy list of fork tube diameters which can be found here) but perhaps the lengths are different ? I haven't checked if the internals have the same part numbers.

At any rate - as Fred says I'm happy with the Cruizinimage fork tubes, and I actually bought two pair ! :D One pair for my '73 GT750 K and a set for the '72 J I'm collecting parts for 8)
Ian

If at first you don't succeed, just get a bigger hammer !
stlrocker
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Re: gt550 fork tubes

Post by stlrocker »

thanks, that sounds like a nice price. the sellers name looked familiar, so i checked and it turns out i just bought a gasket set from him. came pretty quick from japan. he listed the length of the tubes, so im gonna go check mine to see if they match.
stlrocker
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Re: gt550 fork tubes

Post by stlrocker »

my tubes check out the same on length. 62.5cm. so they are the same length and diameter, but the different part numbers have me wondering. does anyone know for sure they will interchange? the price is good, but if they dont fit, it aint so nice afterall.
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oldjapanesebikes
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Re: gt550 fork tubes

Post by oldjapanesebikes »

stlrocker wrote:my tubes check out the same on length. 62.5cm. so they are the same length and diameter, but the different part numbers have me wondering. does anyone know for sure they will interchange? the price is good, but if they dont fit, it aint so nice afterall.
I suspect your best bet is to just sit down with the parts lists and cross check to see what is common and then make a decision. On-line parts lists are available at lots of places. 8)
Ian

If at first you don't succeed, just get a bigger hammer !
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jabcb
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Re: gt550 fork tubes

Post by jabcb »

Need inner tubes for a 72 GT550.

GT550 original part # is 51111-34030
Compared GT550 & GT750 fork damper assembly part #s & found two difererences: spring & inner tube.
GT750 original part # is 51111-31030

Options include:
Frank’s
eBay seller Legend Motorcycles (made in Japan by ???): https://www.ebay.com/sch/m.html?_ssn=le ... uzuki+fork
Tarozzi for GT550: http://www.fastfromthepast.com/05-0701 (listed as 35mm OD & 625mm long)
Tarozzi for GT750: http://www.fastfromthepast.com/05-0494 (listed as 35mm OD & 624mm long)

eBay seller CruzinImage only lists fork tubes for late GT750s

Has anyone used the fork tubes that Legend Motorcycles sells?
Any thoughts or suggestions?
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

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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jabcb
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Re: gt550 fork tubes

Post by jabcb »

Bump -- no input?
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

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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