Topic: CB550 Big bore planning

[MRieck]

I am looking forward to see how it all comes together: 592cc (10.5:1), Keihin CR29, ported head with 3 way valve grind and CB650 cam.  It should make the bike nice and peppy...maybe I will take it to the track this summer and see how she goes.

It will be fun. If you don't mind me being nosy who did the porting?

[akabek]

I am looking forward to see how it all comes together: 592cc (10.5:1), Keihin CR29, ported head with 3 way valve grind and CB650 cam.  It should make the bike nice and peppy...maybe I will take it to the track this summer and see how she goes.

It will be fun. If you don't mind me being nosy who did the porting?

I had a friend of mine do it.  He has done head porting before and he was familiar with vintage bike porting.  On top of that the price was right.

[akabek]

Yesterday I completed the bike.  It took a few cracks on the starter but she came alive.  Since jetting my carbs last fall I now have a 592 big bore, ported head and I added BBR filters to my Steel Dragon velocity stacks as the bike is for street use.  I took a short ride around the block to get a feel for it and although I could not whined it out (with the new big bore kit) it did seem to be peppier.

For the break-in I will keep the RPMs down below 5500 and change the oil around 1000 KMs.  Any other suggestions for the break in period?

The CR29 carbs were dialed in pretty good before the motor mods except it ran rich during idle.  If I drop the floats down will that help with the idle richness?

I will post some pics when I have her running good and add some finishing touches.

[turboguzzi]

Any other suggestions for the break in period?

dont baby it at all. i try to run in motors in the dyno and start aplying full throttler right away

10 runs up to 6K + 10 runs up to 8K + 10 runs up to 10K , done

if not find a really quite open road  where you can do similar "pulls" that last about 10 seconds in 4th-5th gear

[akabek]

Any other suggestions for the break in period?

dont baby it at all. i try to run in motors in the dyno and start aplying full throttler right away

10 runs up to 6K + 10 runs up to 8K + 10 runs up to 10K , done

if not find a really quite open road  where you can do similar "pulls" that last about 10 seconds in 4th-5th gear

Good thing I asked or I never would have thought to use this approach.  I live near a highway so I will break it in there.  After each run should I bring the bike to a complete stop and go again?  I guess I could get on the highway, run the bike up to 5th gear and get off at the next exit and come back the other way.  Should I let the bike cool after a couple of runs?  The weather is still on the cool side right now.

[akabek]

Well I believe I have my CR29s jetted the best they will get.  I need to keep it idling over 2K after it warms up or it dies on me.  I can hammer on the throttle and she goes but it is running rich.  Now I am thinking I should pony up for the CR26 and sell the CR29s.  Will this be a more fitting size carb?  Some stores match the CR29 with the CB550 and others suggest the CR26.  The acceleration is great but my tail pipe is black.  Will my CR29s fit a 750 or would it need new brackets to re-align the carbs for a 750?

[mazen0822]

Any updates on the bike.

[akabek]

Any updates on the bike.

I was chatting with another member that has a CB550 modified similar to mine and he said the CR29 worked better for him than the CR26.  I have the bike running well but my next plan is to sync the carbs.  My carbs have not been synced since I made all the engine mods so hopefully that will bring my idling down.  I should find time in the next few days to sync my carbs and I will post an update.