GT 750 Tranny woes

Danzuki · Post by **Danzuki** » Thu Mar 26, 2009 9:40 pm

Hi everyone...Awesome sight! (Newbie first post) Wondering if any of you Waterbuffalonians can help? I was lucky enough to acquire my 1974 GT 750 back last week that I bought brand new 35 yrs ago. When the bike is cold it shifts like a dream but after about 25 miles it becomes hard to shift out of 5th gear. From this point on the more it's driven it becomes hard to shift in and out of all gears. The tranny oil has been changed and even expiermented with different viscosities and synthetic. Tranny oil is now back to Suzuki specs. Sorry I got long winded. Thanks for your help. Dan

GT Tim · Post by **GT Tim** » Thu Mar 26, 2009 10:05 pm

Is the clutch action smooth or become sticky or notchy when you work the lever when it warms up? If so, I'm feeling the clutch basket is suspect. Could be grooved or out of round. When things heat up the metal expands and tightens up causing the notchiness.

Otherwise in absence of that could be a bent/worn shift fork.

I'm sure others here with more in-depth knowledge of GT750 trannys can give you a good place to look.

Post by **Suzsmokeyallan** » Thu Mar 26, 2009 10:09 pm

Glad to see you here Dan, from your post you left out a few details, but since as you said, the issue gets worse with miles, that also equates to heat of the engine and its oil making it worse.
It could also mean the culprit is not an actual gearbox shaft, selector fork, or cog issue but something else related to its function.
For your first stab into it id take a look into the clutch housing and see whats going on in there.
Things like broken fibre plate(s), grooved or broken basket fingers, slack hub washer/nut are all prone to create a symptom of what youre experiencing.
GTs were also known to blow up clutch baskets after many miles of use so its best to confirm the condition of these parts next.
Keep us posted...

Danzuki · Post by **Danzuki** » Thu Mar 26, 2009 10:29 pm

Thanks guys. (More info) The clutch lever is smooth from engaged to disengaged but seems hard to pull. The bike was layed over on its left side in gravel at about 15 mph 12 years ago. (Yup my brother) Its been mostly restored externally but nothing has been apart internally. 37,000 ori miles Thanks again. Dan

Danzuki · Post by **Danzuki** » Thu Mar 26, 2009 10:41 pm

After you guys both mentioned the clutch housing/basket it dawned on me that 70 percent of those miles were put on the bike when I was 19 yrs old. It wasnt driven by a little old lady. LOL...Dan

jkevinlilly · Post by **jkevinlilly** » Fri Mar 27, 2009 3:58 am

Welcome to herd Dan. Keep us posted on what you find.

Ain't it great to get an old bike back?!

One of the 550's I have I originally bought used in 77, rode for about 4-5 years, sold to cousin, who then sold it to an Uncle, and finally about 4 years ago I got it back. After 18 years of sitting in a basement, and a complete engine rebuild, it is back on the road.

Kevin