Author Topic: Wolfey's 1976 CB550 Street/Track Build  (Read 9638 times)

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Offline Trad

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #25 on: February 07, 2016, 10:43:32 PM »
Are you going to rig up any kind of flow bench after you've finished the porting? Man, you are braver that I! haha. Project is looking sweet dude.
74 CB550 Build: NOS-GUTTED-OEMplus-HOLDTRUE
http://forums.sohc4.net/index.php/topic,130575.0.html

Offline Wolfey

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #26 on: February 08, 2016, 06:54:49 PM »
Wolfey...you've really have me fascinated with this project.   Are you planning to stiffen the frame at all?
I did quite a bit of stiffening to the frame. I braced the frame in the triangle where most of the torsion is. Also right below the air intakes I did a cross bar there as well to limit the torsion of the frame from side to side. I did the brace for the tail light ( 1/4" plate steel) that should help with torsion too. I am also putting a brace in the back for mounting of the back of the seat. Here are some pics to show the bracing.



This one shows the brace just under the front of the seat.

This one shows the cross frame brace where the intakes would be. (Sorry I dont have a better picture right now.

Offline Wolfey

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #27 on: February 08, 2016, 07:04:07 PM »
This is getting good :)  What exactly are you doing with those intake "pockets"?  Hard to tell from the pics.

Spence

Hi Spence,

So I was reading Hondaman's FAQ and he spoke about the flow of the heads in the 550. Here is the link http://forums.sohc4.net/index.php/topic,7401.0.html. So specifically in the section he wrote:

3. In the heads: all of the inline fours except the 400-4 had breathing issues. Grinding a "pocket" above the intake valve(s) and matching the ports to the carb tubes will improve them, especially at high RPM. Polishing the intake valve(s) helps, too. Don't back-cut the intake valves or you'll pop off a valve head - an expensive day, at best. (Backcutting exhaust valves will make them burn, and quickly - the CB650 malady). Trim (narrow) the intake valve guide bosses for a smaller profile, and polish it. Smooth, but don't polish, the intake tract. If you're good at heliarcing, raise a bead about .100" high along the bottom of the intake ports (CB750 only) in a half-moon shape, then smooth it off along the sides so it "restricts" (apparently) the bottom passageway about 1/3 of the way around. The floor of the port should ramp up to it, then be fairly abrupt in fall-off on the valve side. Do this at the point where the intake track bends down toward the valve (no, it's not easy). Although not obvious, this mod creates some "free turbocharging" at RPM above 6000, all the way to 16000 (lots of work), which deals more with fluid dynamics than I will put into this post.

So initially I am just doing a big bore on the engine. I will probably put it all together and just run it this summer as is. Then this next winter I am going to build the top end out quite a bit more with cam, valves, rockers, springs, etc. But to build up to all this I am trying to get the porting on the head done now to help with the response because I would like to track the bike this summer some. I am going to try and get dynos done at each stage too since I dont see many actual numbers and have the opportunity to do it.

Ernie

Offline Wolfey

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #28 on: February 08, 2016, 07:06:11 PM »
Are you going to rig up any kind of flow bench after you've finished the porting? Man, you are braver that I! haha. Project is looking sweet dude.

I hadn't planned on it. Maybe next winter when I build the motor out more.

Haha its only a head right?  ;D

Offline sbeckman7

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #29 on: February 08, 2016, 07:24:37 PM »
Very cool (and interesting), thanks for sharing :)

Offline mrfish2

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Re: Wolfey's 1976 CB550 Street/Track Build
« Reply #30 on: February 09, 2016, 05:37:48 PM »
I'm subscribing to this, interested to see how everything works out for you.
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline FunJimmy

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Re: Wolfey's CB550 Street/Track Build
« Reply #31 on: February 09, 2016, 08:34:22 PM »
My instrument guage I am using.




Interesting project. I really like the instrument cluster and welded cases.
One more than the other though.
You never see a motorcycle parked outside of a psychiatrist's office!

CB550 Cafe Interceptor a Gentlemans Roadster
http://forums.sohc4.net/index.php?topic=27159.0