What won't kill a CB 350?

[Swervin]

I have no idea how my bike was still running! Granted, it was quite noisy, but it didn't run half bad. ;D

The pic speaks for itself. I was blown away how small the guide roller was worn down. It's like a 1/4 the size of the new one!

 

[DrJ]

Yup, that's the weakest part of the motor. Instead of replacing it with OEM parts, you may want to consider this:

http://www.bore-tech.com/CB.html

 

[Roustabout]

On my 350 race bike I cannibalized the steel rollers from a CB450 twin tensioner and modified the 350 tensioner to accept them. The tensioner outlasted the rest of the motor.

 

[Swervin]

Already got it up and running with oem parts, but will go aftermarket when this set wears out.
I'm just glad I caught it before the cam chain wore through the head!

 

[liam]

i have a boretech tensioner in the mail to me.
they were a pleasure to deal with, quick replies to emails to quote cheaper postage to australia etc.

 

[strangedaze39]

I've been eyeing that chain tensioner from bore tech for a while now for my CB350F but really don't want to spend that much money on a tensioner. It looks simple and it's $120?! I suppose if they sell for that and people buy them it's probably worth it.

Anyone know of a good tensioner thats more in the $50 range? I'm trying to replace the chain to, I'll probably just use a CB750 chain for that.

Thanks.

 

[cb350g]

Yup, that's the weakest part of the motor. Instead of replacing it with OEM parts, you may want to consider this:

So how would one know that the tensioner is worn like that? Does it make the engine noisy in some particular way?

 

[Roustabout]

It all ends up in the oil. Check your oil closely when you change it and inspect what you scrape out of your centrifugal oil filter. Look for plastic bits and...... heaven forbid..... metal bits. On my race engines, I would drain the oil into a coffee filter and cut the oil filter apart for inspection.

 

[cb350g]

It all ends up in the oil. Check your oil closely when you change it and inspect what you sc---- out of your centrifugal oil filter. Look for plastic bits and...... heaven forbid..... metal bits. On my race engines, I would drain the oil into a coffee filter and cut the oil filter apart for inspection.

Wait, I'm supposed to change the oil?

 

[Dr.Chris]

I have no idea how my bike was still running! Granted, it was quite noisy, but it didn't run half bad. ;D

The pic speaks for itself. I was blown away how small the guide roller was worn down. It's like a 1/4 the size of the new one!

OK now I'm a complete newbie so maybe am just looking in the wrong place, but I just got the head off my CB350 today and there was no guide roller AT ALL. Zip, nada...

 

[Mark Slide Squad]

I picked up a steel roller from Todd Henning racing for my 1970 CB 350. It's a copy of a Yoshimura unit that was in production back in the day. I haven't gotten my bike running yet, but it will be more noisy with the metal wheel i'm expecting. For sure the stock rubber wheel is one of the weak links of the motor as well. As others have stated it falls apart and the rubber bits end up in the oil supply, get into the bearings and in the oil pump. Not good. When you replace the chain roller you should replace the timing chian too with a "Tsubaki" brand. All the CB 350 vintage racer guys swear by them. The stock timing chain tends to snap under heavy loads/high revs.