GS750 runs too hot!

[Guest]

Hi guys. So i have this 82 750. I went touring on it last year with a buddy, but whenever we rode lots of highways the bikes temps would climb to an indicated 320 on the gauge.

Id like to go on another trip this summer but with the temp issue sorted. As far as i can tell, there are a few things i can change - but i need a bit of guidance on them.

1. Bike running hot because of lean tune -- i think a rejet woukd belp but i dont want to go with a dynojet kit because of price. Have people just gone up a size on the main/ spaced the needle? Other strategies? I have the stock air box and paper filter.

2. Bike needs an oil cooler -- this is straightforward enough, but do people think the rejet alone would solve my problem? I don't want to throw money at the issue.

3. Smaller rear sprocket to decrease highway revs-- i dont understand why these bikes didnt come with 6 gears. Has anyone done this? What were the results ?

Thanks!

[Mercaholic]

I wouldn't trust any of the factory temp guages.

[mrbill5491]

Have you check the color on your spark plugs? What wt oil are you using and the type? Are talking about the oil temp? I had once read in a bike magazine that using an oil cooler on a friction bearing motor like the 750 wasn't a good idea, they said it would drop your oil pressure (don't remember how much) and it was possible it would starve the top end.

I live in a very hot summer area and I'm pretty sure my bike has run well over the temp you posted. Where was this area you were riding when your temps started climbing?

[mvalenti]

Interesting thread, not to hijack, but if one were to take readings on the engine, where would the best place be?

[mrbill5491]

Good question. The cylinders or the head?

Interesting thread, not to hijack, but if one were to take readings on the engine, where would the best place be?

[duaneage]

The oil. I use a thermo couple on a Fluke meter to measure fluid temperatures.

[gearhead13]

I wouldn't trust any of the factory temp guages.

This.
I swapped out mine for another gauge with less miles on it and temps showed dropped by half.

[Nessism]

Oil temp gauge on my first 1000S was accurate. Verified by placing the sensor into boiling water and the indicator read 210F.