Topic: Carb Insulator Leaking Question (1981 CB650C)

[F16Viper68]

I have a 1981 CB650C I've been slowing resurrecting and I have a question.  I noticed the #1 cylinder doesn't always fire (carb's rebuilt, new plugs, has spark, compression good) so I started checking for an intake leak and sure enough the #1 insulator is leaking (RPM increase with starting fluid).

The question I have is will this prohibit the cylinder from firing?

Also I'm finding the carb insulators online for $16.26 and the bands for $8.32.  Does anyone know of where I can get them cheaper?  Or is this as good as it gets? 

Thanks in advance. 

Dave...

[Steve_K]

For a bodge, try wider hose clamps.  May tighten the insulator enough to run better til you replace them.
Cheap fix, one clamp and you know if thats the problem.
Steve

[Doggie]

I have a 1981 CB650c also and I have my insulators soaking in power steering sealer fluid to soften them up
while i'm rebuilding the carbs. Might make them soft enough to make a good seal. Good luck.
                                                           Doug

[F16Viper68]

For a bodge, try wider hose clamps.  May tighten the insulator enough to run better til you replace them.
Cheap fix, one clamp and you know if thats the problem.
Steve

Not a bad idea. I noticed they are cranked all the way down. 

[F16Viper68]

I have a 1981 CB650c also and I have my insulators soaking in power steering sealer fluid to soften them up
while i'm rebuilding the carbs. Might make them soft enough to make a good seal. Good luck.
                                                           Doug

I'm really not sure anything's going to work since I notice cracks on the engine side of the insulators when I was rebuilding the carbs.  Just another part of the puzzle that is this bike.

Off to Ace Hardware to buy some stuff to help me replace the fork seals on this thing.  Seems the 81 CB650C fork seals are different than most.  First time I've seen the manual say "take to dealer".   

[fmctm1sw]

That price may be as good as it gets.  I bought mine from motogrid at about that price.

[Mainerider]

No need for you to take it to the dealer for the front fork service. I have an '80 and a friend has an '81. The only difference (and I've replaced the fork seals and bushings in both of the bikes) is the air hose fittings for the air-assist front suspension on the '81.  It slows you down a few minutes because you have to remove the crossover air line but that's about it; both models are the same, bushing-inteference fit design.

 Read the manual carefully on the air line removal; not difficult but it's easy to get confused over which part of the fittings to turn in which direction.  Really, it's no more difficult than changing the seals on the  79 and 80 forks; especially if you have the proper bushing/seal driver to use. Let me know if you need any more help; I've replaced several sets on various CBs and other models. 

[F16Viper68]

No need for you to take it to the dealer for the front fork service. I have an '80 and a friend has an '81. The only difference (and I've replaced the fork seals and bushings in both of the bikes) is the air hose fittings for the air-assist front suspension on the '81.  It slows you down a few minutes because you have to remove the crossover air line but that's about it; both models are the same, bushing-inteference fit design.

 Read the manual carefully on the air line removal; not difficult but it's easy to get confused over which part of the fittings to turn in which direction.  Really, it's no more difficult than changing the seals on the  79 and 80 forks; especially if you have the proper bushing/seal driver to use. Let me know if you need any more help; I've replaced several sets on various CBs and other models.

Yeah it wasn't too hard once I figured out the process.  I guess they figure nobody has a press/clamp? 

http://forums.sohc4.net/index.php?topic=98191.msg1100717#msg1100717

Dave...

[cb650]

Can u post where and the part # for the insulators.  I need a couple.

[F16Viper68]

Can u post where and the part # for the insulators.  I need a couple.

http://www.cheapcycleparts.com/model_years/88-honda-1981-650-custom-cb650c/assemblies/1424

Insulators: p/n 16211-460-770 $16.26
Bands: p/n 16219-422-000 $8.32

Dave...

[cb650]

Cool thanks.  Latest bike needs a couple replaced.