Topic: Project 72 CB500. From rust to lust!!

[JAG]

Oh yeah that looks great! Ill definitely have to go that route with th build.

[traveler]

Irregardless of any marking on the sprocket...count the teeth.  It is more expensive, but changing the rear sprocket is preferrable to changing the front.  Smaller front sprockets can bind the chain, thus shortening chain life.  O-Ring chains can also cause clearance issues...so stay with a standard chain.

It all comes down to intake, exhaust, timing, and gearing.

~Joe

[Kemp]

Stock gearing on a CB500 is 17/34, 530chain, 98 link. One cheap way to increase performance is to use the rear sprocket from a CB550 (17/37 and 100 link 530chain). If you need to buy new chain and sprockets go with Sprocket Specialists and get a 520 chain combo in 17/37 which is lighter and lets bike rev faster. The added teeth gives you a bit more acceleration with only a slightly higher rpm at cruising speed. This all helps the 500 as it needs to be rev'd as it's power and torque are high up the rpm band. less restriction on intake and exhaust help this little guy a lot as would a 650 cam. Critical that the carbs are clean and sync'd to get the most performance and a little advance on ignition livens them up (5 degrees, set points contact break at "T" instead of "F").

[JAG]

Stock gearing on a CB500 is 17/34, 530chain, 98 link. One cheap way to increase performance is to use the rear sprocket from a CB550 (17/37 and 100 link 530chain). If you need to buy new chain and sprockets go with Sprocket Specialists and get a 520 chain combo in 17/37 which is lighter and lets bike rev faster. The added teeth gives you a bit more acceleration with only a slightly higher rpm at cruising speed. This all helps the 500 as it needs to be rev'd as it's power and torque are high up the rpm band. less restriction on intake and exhaust help this little guy a lot as would a 650 cam. Critical that the carbs are clean and sync'd to get the most performance and a little advance on ignition livens them up (5 degrees, set points contact break at "T" instead of "F").

This is Really great info! Thanks for the tip, I'll have to look into it. I know for a fact it is going to need a rear sprocket anyways.. So maybe a rear sprocket, the increased airflow and advanced timing might do the trick..

Not much else going on right now. Polishing up some covers, and painting the engine. It's been kinda of hard for the engine paint because it's cold and raining outside. This is just the first coat of paint, and first buff on the two covers, still have two more steps on each part to get it perfect..

[JAG]

Anyone know where this start trek emblem goes?? I found it while pulling off the left cover where the shifter is..

There will be more to come. The usual before and after paint and polishing pics, as well as some de rusted parts.

Thanks for stopping by.

[JAG]

Does anyone have one of these lying around they dont want... i don't think there is any hope for this guy.. If anyone wants to use it for some project, I'll trade ya.

[TwoTired]

The pinstripes- do they go around like where the black circles are now? Do you have any pics you can share? If it looks good with The paint scheme that I have I would love to get some from you to finish the look.

Topic has been discussed before...
http://forums.sohc4.net/index.php?topic=5806.msg54228#msg54228

[JAG]

Anyone know where this start trek emblem goes?? I found it while pulling off the left cover where the shifter is..

There will be more to come. The usual before and after paint and polishing pics, as well as some de rusted parts.

Thanks for stopping by.

Just getting ready to put the engine back together.. Anyone know or can help me to figure our what this Leonard Nemoy, Spock, piece is?

[TwoTired]

Looks like the piece that holds the clutch adjuster to the cover (the part with the big slot in it).

Maybe part #6 here:
http://www.cmsnl.com/honda-cb500-500-four-k2-us_model461/partslist/E++11.html

[JAG]

Thanks TT.

You have always been a big help!

 

[JAG]

Been hustling trying to get everything shiny again, and I'm catching a few snags here and there...

I can't seem to clean up these spokes any, so it looks like I will have to buy some..  Will them same that goes on the 750's work on this 500? The only places I am seeing them is at partsnmore and ebay. The wheels are seemingly the same size, I just wanted to make sure..

The link is here..
https://www.partsnmore.com/cat_index.php?model=cb750_sohc&category=chassis

I was also curious about putting on an oil pressure gauge. Do the 500's have the same plug, like the 750's do by chance??

Thanks alot guys..

[theofam]

JAG, the build is looking good so far!  I'm psyched for you that you got it running so quickly.

After reading your thread, I've posted the same spokes question on my thread.  Those cadmium spokes are MUCH cheaper than the stainless steel spokes I've priced.

Can't wait to see more!

[JAG]

JAG, the build is looking good so far!  I'm psyched for you that you got it running so quickly.

After reading your thread, I've posted the same spokes question on my thread.  Those cadmium spokes are MUCH cheaper than the stainless steel spokes I've priced.

Can't wait to see more!

Thanks a whole lot, I do appreciate the kind words. It keeps me motivated!! If you find out anything on your thread let me know, and Ill do the same.

[JAG]

Still looking around for some parts to complete the build process, so it's slowing me up a bit. And I've also been brutally sick for the past week with a sinus infection..

But I finally dragged myself out to the garage today with our 60 degree weather and got the engine in the frame.. I finally tried to put the engine on it's side and slide the frame over top of it, and it work like a charm, with little to no scuffs on my new paint..

I am going to go ahead and replace the rear sprocket and chain with the 550 setup. Found some sets on ebay for around $80.. However I don't understand why I wouldn't replace the front sprocket as well.. Can anyone explain this to me..

Looking at my old sprocket it has wore unevenly. Couting the links and teeth, the rear sprocket had 44 teeth and the chain was either a 101,102 link, can remember which. So that tells me a PO replaced one without the other, or replaced both with incorrect parts. Can anyone shed some light on this issue for me?

Also, one of the steering stops is broken off, and  I was going to tac weld a new stop. I wasn't sure what to use. I was thinking of using a bolt with the threads and the head cut off.. Seems redneck but it may work. Any suggestions on this dept.?

Well after going to the Doc today, and getting some antibotics, I hope to pick back up on this tomorrow.

Thanks everyone for stopping by.

[TwoTired]

The CB500 has a different primary reduction ratio (2.000) than the CB550 (3.063).
Best to use the stock ratio sprockets front an rear on the CB500. 17T front and 34T rear. (Unless you are into drag racing and don't mind the engine screaming on the freeway.)


Because of the smaller number of teeth, the front sprocket generally wears faster than the rear and therefore need more frequent replacement.

If the valley of the teeth on the sprocket have worn to the spacing of a worn chain.  A new chain will quickly wear to the spacing of the worn sprocket, meaning it wears out the chain faster.