CB175 Camshaft Endplay

P

pacomotorstuff

Coast to Coast
Hi everyone,
Continuing the trudge on the Dad 'n Daughter Tiny Tracker, I'm reassembling the head after new guides, seals, valves, springs, retainers - brought it as close to brand new as I could.
Anyway, with the camshaft in the head and the 2 camshaft bearing plates torqued down, I measured .025" - ie, 25 thou end play in the camshaft, moving it back and forth across the head, if you will, using a feeler gauge. The bearing surfaces in the endplates are good, there is no evidence of the either end of the cam wearing on their respective cap and the cam doesn't have any slop when rotated - just back and forth across the motor.
Never worked on a CB175 before and wondered whether this is normal - maybe to let the cam sprocket line up with the crank sprocket or something (I haven't put the head on the motor yet, so don't know about camchain alignment).
The manual I'm using, makes no mention of this, so if someone could let me know, that'd be great
Thanks,
Pat
 
these are very similar almost exactly so in design to the cb350
on the 350 from memory you want quite a bit less than that i set mine up to .006" with great results
i had been running it at .035"(before i was aware of proper setting) and it was noisy as fuck, also having less clearance probably keeps a greater amount of oil pressure to the bearings
you can shim or just remove the gaskets and use 518 loctite/permatex
you can also face off the gasket surface in a lathe

the clearance actually grows a bit as all the parts heat up
the clearance is not needed or a good thing for chain alignment
the sprockets are such a distance from each other that some axial mis alignment is harmles to a certain point of course
the best way to sceck is with a dial indicator it is easier than a feeler gauge as you can put the dial point axially to the cam from the points acces
 
Did you have gaskets installed on end bearings?
Shims used to be available plus thinner gaskets to reduce end play. It's a real long time since I worked on 175's though
 
After vacillating about the endplay, I tossed the head in the truck and drove up to my machinist's place. He had a good look at the head - with all the work done to it, it looked like new - and opined that, if the manual doesn't have a spec for it, just run it and do frequent inspections during the break in.
So, the rebored cylinders and the head went together Friday night and the camchain installed on Sat morning. I bought the HD (heavy duty) version of the camchain, so I'm putting the arm on another friend to use his special tool to set the rivets on the master link for me.
I'll keep you posted.
Pat
 
you should have reduced it , is one of those things that can actually vary on new parts
and it is an incredibly easy thing to do
your machinist simply isn't familiar enough to know any better , i woont follow his advice anymore
 
Did you check for wear at the cam journal -- the end where the tach drive is? These commonly wear if they run low on oil, if they run dirty or old oil, or if you lose some oil pressure -- oil directly lubricates it without bearing. IF it's bad, you can see scoring or evidence of heat/wear, but not always.
 
That's the damnable thing about the issue - the journals both left and right show no scoring and the radial clearance is minimal - like, you can't feel any.
Every Honda manual I've checked in the last week doesn't even mention the issue (and I've read a lot of them) - how to check it, anything...
As far as "not listening to my machinist anymore", um, er, while he is a pretty low key guy and pretty hard to track down, he has been doing this sort of thing for 40+ years including some contract work for a little Japanese company you may have heard of called Honda...
Pat
 
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