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Hi all:

OK I have been refurbishing a 1981 Yamaha XJ750RH Seca, I have finally gotten it on the road and while doing my shake down run it seemed to me that in 5th gear at about 38 mph with the motor at 3000 rpm the motor and gear box wanted another gear to go up. I have not driven a bike this old so I am not really familar with this type, I drive crusiers that have a OverDrive gear for highway use.

I have gotten different views by some riders around me but ah i just wanted to ask a larger pool of information.

Thanks for your time

W.Broad

My 82 CB750K turned much lower rpm's than that as I recall, it replaced a CB400T first bike that turned about 6k @ 60 mph and I thought that was way too many revs. My 750 was a 6 speed and I think that was why the 750s were going to 6 speeds around that time, about 30 years ago.

Now and for the past 15 years and 180k miles I've been riding a couple of GS500s that are geared to turn about the same revs as your 750 and it seems quite normal to me now. Have done quite a few 400-500 mile interstate days at 70-80 mph on them and find the revs quite normal now.

If you had a chain drive you could add a tooth or two to the front sprocket to bring the revs down at highway speeds but yours is a shafty I think. Perhaps a larger dia rear tire would fit to bring the revs down a bit. You'll probably get used to it as is if you ride it a lot as I did with the GS500s. They've been too much fun to worry about the revs being turned.

Hello William and welcome to the forum. Your Yamaha's "sweet spot" is between 3k and 5k rpm. IOW let your rpm's go-go. Show us a picture of your Seca.

Thanks guys for giving me an answer.

This bike is a shaft drive and I put on, OEM sized tires for it. Going to check compression and check valves then do a carb sync.

I'll get a picture upload soon of her.

W.Broad