wont rev past 55-6000 rpm

[TXterror]

hi guys let me jus start by saying thanks to all of you that have helped me along.the way to try to get this bike running right. bike is a 1980 cb650c with pods. main jets are 120 and slow are 42 pd carbs. ive cleaned the carbs a couple times and checked the tank before cleaning em. the problem im having is that i can get her passed 55 - 6000 rpm or 60mph. also i noticed that she runs and pulls harder when i have the choke pulled out but still wont pass 6k rpm. upon start up she idles around 1200 rpm and after riding for a bit she will begin to idle round 2000-2500 rpm. but that isnt my main concern, i wana fix the stumbling in high rpm's. i took her out for a spin and pushed her as much as she would go and came home and pulled the plugs. which all looked tannish white color, i also touched all headers and they were all pretty hot to touch. i recently cleaned the advancer and set timing dynamicly and bench synced the carbs. i am stumped on what to do next, this is beginning to get on my nerves. im gettin close to just take the damn thing to a mechanic so i can stop playing the guessing game. any help and advice welcome. i need to get some pics up soon and the renderings i did on what i want to do to her once i get her running good. i can feel it im almost there

[onepieceatatime]

I think the pods are your problem.

You may want to check this thread:

http://www.hondacb650.com/viewtopic.php?f=4&t=773

[TXterror]

forgot to mention that i also tried the loose gas cap trick too but didnt make a difference.

[Volker_P]

If you have pods, white plugs, hot engine and things go a bit better with choke you may still just need larger main jets.

[TXterror]

Plugs arent ghost white, more tan than white. The engine is hot but i was refering to the exhaust off the heads that i was touching. Do you think i should go back to stock air box? Bike came with pods but stock airbox came with it aswell but in pieces and im not sure what all goes where. As far as where tubes connect. Also the big rubber chuck that connects to the air chamber (largest boot) is very loose and comes off fairly easy. Dont know if this is gonna be a problem

[Volker_P]

Charging is all right? Did you try new plugs?

If you checked the typical issues like timing, ignition, valves and running out of ideas the stock airbox is no bad idea. Stock PD carb main jets are 90-95 however.

For the plugged side of the airbox boot, one may try to make an inner support clamp that keeps it open and tight

[TXterror]

Plugs that came with the bike look new. How would i check the charging system? Also what would i look for when inspecting valves. Only thing that sux if i go back to stock air box i will have to buy stock main and slow jets. And as far as the ignition goes, is there more to it than just lubing up advancer. Sorry for the noob questions but this all new to me. Thanks again for the help, greatly appreciated

[Volker_P]

Measure charging voltage, should be around 14V or a bit more at 4000rpm. As a rule of thumb, charging is all right if you see the headlight getting brigther when you rev up from idle.

For the valves, first do cam chain tension. You may verify it directly at the chain with a screwdriver with the center valve cover removed. Then check valve settings with a feeler gauge.

Ignition timing may be verified and set if required. The static method described in the manual linked below is sufficient, just check if the advancer moves freely.

[anglia4]

I had an almost identical problem with mine.

It just wouldn't rev past 5500rpm.

I re-kitted the carb and it got slightly better but was still really bad. Turned out the biggest problem (at least after I did a carb kit) was that the floats were not set correctly and it was running out of fuel.

[TXterror]

Well so far i have set valve clearance, checked and lubed advancer, set timing, cleaned jets except slow jets, adjusted cam chain tension, and set floats to 12.5 mm but bike still wont rev past 5000 rpm in fifth gear. I noticed while riding it the other day that i was able to go faster in forth gear than fifth(passed 50 mph). fifth gear is where it stumbles. Get into fifth gear and it just stumble at 5K rpm. Should I jus give up and take it to a shop, where they will rape me (money wise) or should i continue to play the guessing game?

[TXterror]

bigger pic (forgot to put on my side covers)

[cb650]

Double check the float height. And you might be to big on jets. Try 110 and see if its better. Check out pinheads bike and see what he is running.

[Volker_P]

So what happens if you very slightly pull the choke at 5500k at 5th?
And what about the charging voltage?

[TXterror]

Bike still stumbles with choke pulled. As far as charging, only thing i checked was battery and it was good.

[TXterror]

I misread your post volker, havent tried pulling choke when it starts stumbling. I will try this evening and post results.