1976 CB550 HELP

[Erik_CB550F]

OK, I NEED HELP ON A COUPLE OF THINGS.

1) I'M HAVING MY CARBS REBUILT, AND IVE ALREADY ORDERED POD FILTERS FOR MY BIKE BUT I DON'T KNOW THE PROPER JETTING SPECS JETTING SPECS? (LIVING IN SO-CAL)

2) I DID A COMPRESSION CHECK ON MY BIKE, AND THE NUMBERS WHERE 160,150,135,155.. IN THAT ORDER FORM. I PERFORMED A LEAK DOWN TEST, AND I DID NOT SEEM TO FIND A LEAK. I ADDED A TEA SPOON OF OIL ON THE #3 CYLINDER, AND THE COMPRESSION SHOT UP. ...... ANY SUGGESTIONS????? I WOULD LIKE TO TRY OTHERS THINGS BEFORE TAKING THE HEAD AND CYLINDER OFF TO HONE AND RE-RERING THE PISTONS..

3) WHERE CAN I GET A CAFE SEAT FOR THIS BIKE???

THANKS GUY, ANY HELP IS DEEPLY APPRECIATED ;D

 

[Erik_CB550F]

not one reply

 

[swan]

OK, I NEED HELP ON A COUPLE OF THINGS.

1) I'M HAVING MY CARBS REBUILT, AND IVE ALREADY ORDERED POD FILTERS FOR MY BIKE BUT I DON'T KNOW THE PROPER JETTING SPECS JETTING SPECS? (LIVING IN SO-CAL)

2) I DID A COMPRESSION CHECK ON MY BIKE, AND THE NUMBERS WHERE 160,150,135,155.. IN THAT ORDER FORM. I PERFORMED A LEAK DOWN TEST, AND I DID NOT SEEM TO FIND A LEAK. I ADDED A TEA SPOON OF OIL ON THE #3 CYLINDER, AND THE COMPRESSION SHOT UP. ...... ANY SUGGESTIONS????? I WOULD LIKE TO TRY OTHERS THINGS BEFORE TAKING THE HEAD AND CYLINDER OFF TO HONE AND RE-RERING THE PISTONS..

3) WHERE CAN I GET A CAFE SEAT FOR THIS BIKE???

THANKS GUY, ANY HELP IS DEEPLY APPRECIATED ;D

1. I used 115 main jets for my old CB550F, pods, 4 into 1 exhaust at an elevation of 700-1000 ft above sea level. She ran beautifully throughout the throttle range. A vacuum gauge will dial in the final tuning and balancing.

2. Check factory service manual for specs on compression. I would retorque head bolts to factory specs to see if number 3 cylinder pressure will come up a bit.

3. Seats are available on E-bay, a few vendors or make you own. Try Glass from the past http://www.gftpstore.com/Seats_c6.htm ,Airtech http://www.airtech-streamlining.com/vintage/vintageseats_round.htm or Disco Volante UK http://www.discovolantemoto.co.uk/bodywork/seat-unit/prod_1016.html or Take a look a Benjie's but IMHO they are expensive and look too modern.http://benjiescaferacer.com/parts.php

Good luck and post your results!

 

[Erik_CB550F]

Thanks Swan i checked compression again today, and it was at 165,170,155,155. I also went ahead and did a leak down as well, but i couldn't find the problem.. I work at a motorcycle dealership, and my friends said it might be fine, but i don't know.

Im going to go ahead and try that jet size recommendation. I just received my carb rebuild kit, along with the club man bars.

this is the seat i chose

 

[mmatt34]

I wouldn't worry too much about those compression numbers. They really don't look that bad. If you a compression test on a bike that's been sitting for a long time, those readings will probably change (for the better) after you put a few miles on it anyway. I would adjust the valves, which will effect your compression if the clearances are not to spec. My advice would be put your carbs back on, do the entire 3000 mile tune up checklist thats in your manual and ride her . Then do your compression and leak down tests if you think it's necessary.