Cafe Racer Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Hey guy's im new to this site, been looking for a good bike forum for awaile. I have a 1986 Honda Cb700sc nighthawk. "cafe racer styling"
I absolutely love this old bike. I am trying to get the most out of it performance wise. I am a student at a technical school becoming a diesel/industrial technician and have been around cars and bikes for awaile

the bike has a factory pro jet kit, i cut the snorkel off the air box, removed exhaust baffles so far. Bikes run's pretty strong, started off runing 115 main jets stock , now its at 122's. there still a little large but the weather is getting cooler and its getting better by the day. I live in arizona so 90-100 degree days are very common so the bikes likes to run leaner that what its jetted for. I was wondering what the next steps are performance wise? the compression is rather low at 9.3:1. Combustion chamber's are excellent designed. Nice quench pad's and generously sized valves. I was thinking about going individual filters but friends that are motorcycle tech's say they can be a headache tuning wise. stock the bike is rated at a 12.3 in the 1/4. Whats your advice, opinions, ect. Thanks!

there isn't a change you make to an engine that doesn't make a difference, it's just up to you to figure out what that difference was.
 

·
Registered
Joined
·
2,047 Posts
If I remember correctly (been a while) we shaved 30 thou off the head of my old 700 and didn't have any valve interference, that bumped it up a fair bit, however I was also running a set of cams. Without the cylinder pressures could exceed 300# and that as you know.....would be bad.

I also ported the head, more of a cleanup really and ran an aftermarket exhaust, we decided that the stock pipes were a bit restrictive. Never had an issue with pods on mine either so go for it.

The silly thing ran like a beast and regularly made liter bike looks silly stoplight to stoplight. Have fun!

Lead, follow or get out of the way!
 

·
Registered
Joined
·
2 Posts
Discussion Starter #4
Awesome! yeah where did you find a set of aftermarket cams? i think milling the head is a good option but will throw my timing off unless i get adjustable cam gears right? Swagger let me know if u can help me find some parts to awaken this beast. I think an aftermarket 4-1 exhaust coupled with individual filters and a milling the head would prolly put the motor somewhere around 100-110 hp at the crank. I hope i can get the compression close to 10:1-10.5:1 Hopefully some other people will step in here and help out. Thanks

there isn't a change you make to an engine that doesn't make a difference, it's just up to you to figure out what that difference was.
 
1 - 4 of 4 Posts
Top