[CresentSon]

I'm afraid my CB400-T1 Hawk is gonna be on hold for a while. Frankly this guy is closer to running...

Post from DTT

CB750-F3 I'm callin' The Filthy Beast. I just picked it up last Tuesday, but its a real snotter.

The ad in the paper said "runs good" which is code for needs carb tuning, pops, sputters, smokes, and leaks. The duck tape seat and custom "rebel sportsman" sissy bar gotsta go.

She has sooooooo much potential though.

Down to brass tacks. I've been on full lurk mode and I think I've narrowed it down to:
1 fuel mixture is rich
2 shade tree "mods" to stock air-box
3 carbs need syncing

I already set points and timing and gave the carbs a light cleaning, although I'll have to rip'em back off and check the pilot jets. I just gave them a quick spray through with carb cleaner and kinda regret not being more thorough. She still is having idle issues so I'm gonna set the fast idle and idle. Any thoughts or suggestions would be appreciated. I have a 78 CB400-T1 completely torn down waiting on a valve job and rings, but this one is gonna get a quick & dirty so I can get my knees in the breeze now. The plan is to get the 750 on the road, get the 400 cherry, and then hit the 750 again.

 

[sakibomb]

I have never been a fan of sissy bars. Just makes the bike look stupid 90% of the time. Aside from that your right, its really not that bad off.

Get the engine running smooth and maybe check out the ign but aside from that i bet its a sweet ride. How much did you have to pay if you don't mind?

 

[CresentSon]

I thought that I paid too much at $700, including the 80 mile delivery by truck, but she just keeps surprising me as I get maintenance done. I started with the carbs, set the timing, played with the fuel mix (still rich), did a quickie sync (had to test the manometer I built), and adjusted the valves. She is still weak on the top end, but it just keeps getting better and better.

Funny thing is, the guy wanted $1000 without knowing what he was really looking at (Harley guy who doesn't do any of his own wrenching). I told him on the phone before I made the drive I wouldn't go over seven regardless of condition. Almost talked him down more when I got there and she wouldn't start, but I'm glad I didn't hassle him because he just had the switch in the wrong position.

On the whole I'm very pleased with the performance, just gotta keep on tweaking.

 

[kirkn]

Keep up the good work! Sounds like a great find. Looks like you've got a great little helper there, too!


I enjoyed my '78 K8 while I had it:

 

[66Sprint]

Daniel, Note that minor changes in the 77/78 sohc model made them smoother but they didn't have the "initial grunt" feel or as fast a top end as the earlier bikes....

 

[CresentSon]

The top is almost flat, I can squeeze 70 out, but it feels like I'm pushing it. If I can get to a steady 70 I'll be happy. This will be my commuter and highway speed is a must out here in the country. With narrow shoulders I really don't want to pull over to let a Mack pass. It's windy enough as it is without being gusted into the ditch.

 

[66Sprint]

You should check compression! ....I can get 80+MPH out of a 175cc twin with a stock engine (20HP)....admittedly, that's topped out, but still.....

 

[tbpmusic]

That bike should do an honest 100 mph.....

 

[Bird76Mojo]

Hell my old K8 would do a respectable 120 with ease. I miss her terribly.

GB :mrgreen:

 

[CresentSon]

She still has a lot of issues to work out. I haven't checked compression, but the way she'll jack my shoulders out of socket on take off makes me doubt that's the issue. Admittedly, I "know" exactly squat, but I'm a silver lining guy. On the other hand, I haven't gotten her much over 6K, and I'm still new. In fact the 25-30 miles I've put on this last week are my first since high school, so maybe I'm the one with problems pushing past 70. She may handle it great. Maybe I might just need to feed her more on the low end?

Hell my old K8 would do a respectable 120 with ease. I miss her terribly.

GB :mrgreen:

I feel you pain brother, just let it out. Somebody get this dude a tissue...