increasing HP on 750a

[notn]

Has been a while since I have visited the site. I am a c-6/7 quadraplegic with a 1977 cb750a (hondamatic) trike. It is still work in progress but have over 1000 miles on it past 2 summers. My issue is that the trike, me and powerchair weigh in at just under 1500 pounds. That is a little much for the 750 to drag around especiall up our hills. I have considered the 830cc kit but would like some experience advice here. What is the best /easiest way to increase the HP on my old bugger. it sure needs some umph at times. We have played with the gearing but it still comes back to HP. Any comments on the 830 kit (or any other), carberation, whatever would sure be appreciated..Thank you notn/neal

 

[dirtdigger]

For the most part you can do any of the standard 750 motor mods to the auto. The auto's had smaller carbs, detuned camshaft and slightly lower compression then the standard motor. The 836 kit will bump displacement as well as get compression up to 10 1/4 and they can be used with a stock bottom end, but you may or may not have to use premium fuel. Any more displacement and you would have to start upgrading more internal motor components. Easy bolt on mods that do make a difference would be to swap in a K motor camshaft of a smaller aftermarket camshaft. The auto carbs are considerably smaller then the k motors and it is common to swap on earlier k motor carbs. You would need the carbs and the rubber intake tubes and either the airbox or some other filter setup.

 

[notn]

thanks dirtdigger

For the most part you can do any of the standard 750 motor mods to the auto. The auto's had smaller carbs, detuned camshaft and slightly lower compression then the standard motor. The 836 kit will bump displacement as well as get compression up to 10 1/4 ....

thanks dirtdiger. I think I have access to some "K" carbs and will check out the kits a little closer, I think there are a couple different manufactures. Appreciate the info for sure.
Neal / notn

 

[dirtdigger]

APE, Dynoman, and Cycle X all sell big bore kits. Please stay away from the cheap ebay 836 kits, there dimensions are not terribly accurate and most of them are cast pistons and not forged. There have also been issues with lower piston height which reduces compression. In the past I would have recommended Cycle X but I am now dealing mostly with APE, they can do all the machine work and have very good customer service. They just dont offer as many speed parts for the 750 as the other companies but Jay the owner has been building these motors from the beginning. Any questions be sure to ask.

 

[Brad426]

Gedday, I'm in the same boat as you. I'm C5/C6. I have two CB750A's and a GL1500SE so I'm big into modifications for folks with mobility issues. Lets hook up.
Brad