Topic: CB750K4 - clunk from the front and Sealed battery issue

[andy750]

Steering head bearings - clunk clunk..
Sunday I checked the steering head bearings after installing Alls Ball bearings over the winter and riding for about 50 miles. There was a clunk coming from the front end when coming to a stop or sometimes when hitting a bump. So checked them and they were loose - no problem tighten them up. Rode last night - nice and firm. Rode to work today -4 miles each way. On the way home..clunk again...checked the front wheel this time..a very small amount of free play from front wheel - how much should there be - front bearing perhaps? However then I checked the steering head nut again and again it was loose...??...so this time I went through every nut and bolt and tightened again...all firm now...havent had a chance to test ride yet but....why would it "unwind" itself?

I followed Johnies instructions per the photos and all spacers seemed to be in the right place....anyone else come across this?

Some photos after its all tightened up....

The K4 - is it seating correctly?




But looks the same as the K2 (which has been untouched!)






AGM battery...last year my 2 yr AGM battery went bad and I replaced it with another one - same make from Advanced Auto...in the meantime I replaced the K4 harness as it was old (not really relevant here but worth a mention possibly). Tonight I find my 1 yr AGM battery is not holding charge...I suspected it was going bad as the battery tender couldnt get it to charge either (but the other AGM battery I have charged fine so its not the charger). Bad batch of batteries or should I be checking something on the bike?

thanks for any thoughts on this...was hoping to go to a Vintage bike show in NY state on the K4 this weekend but looking unlikely at this point.

Andy

 

[Alan F.]

I had to adjust the steering bearings on my 92 nighthawk earlier this spring for the same reason. I had probably 10,000 miles on them and was noticing that 'clunk' I know for fact that the nut on that bike didn't loosen itself as the top nut has a tabbed lockwasher sandwiched with a checknut, just torque it and bend the tabs up and down to keep things in place. I'm not sure how long mine was out of adjustment, maybe it was all my spring riding on potholed highways that helped set the races a little tighter in the neck? But I raised the front of the bike and tightened it up until I couldn't feel any 'clunk' while pulling on the front wheel.
About a thousand miles later, yesterday while I had it all apart to rebuild the forks I checked again for any play in the steering that I could feel, I found none. The slight preload I had worried about seemed to be gone too.

So in short it's probably just your tapered roller seats settling into place in the neck, no
You could always mark the orientation of the top nut with a permanent marker if you still suspect it.

[Johnie]

Andy...I don't think it loosens up, but just needs to be seated a few times since it is new. I will need to do mine again which will be about 300 miles from the last time. It will be the 2nd time I tightened it. At least it is easy enough to do. I probably could have gone a little tighter last time, but I did not want to overdue it.

[andy750]

Ok thanks Alan and Johnie. Ill keep an eye on it.

I do have some play in the front wheel axle though (when bike is on centerstand) and concerned that it may be a wheel bearing. Further investigation required here....


cheers
Andy

[Inigo Montoya]

Andy, is it possible that your regulator is not working right? Too much voltage being fed to the battery maybe? Otherwise maybe too much vibration somehow but that usually does not affect agm. bad batch is probably the last option.

[andy750]

Andy, is it possible that your regulator is not working right?

I was wondering the same myself...I think Ill be upgrading to the combined regulator/rectifier in the near future...

[Inigo Montoya]

I would like to do that as well. Save a little room and less wires hanging around. I feel that the elctronic regs charge better and at lower rpms, imo.

[Spanner 1]

Andy, the thing about head bearings and adjusting them is that the pinch bolts on the lower tree need to be loosened before you adjust/tighten the steering head nut as your pushing the upper and lower tree closer with tightening the head-nut...I read that somewhere.
Don't forget to tighten fork pinch bolts when adj. done...!!

[andy750]

Thanks Ray for the reminder but last night I did all that - I was being extra thorough as I have been known to miss things like that now and again . I rode to work today hitting all the bumps I could and Ill have another test ride on the way home. Heres hoping it remains ok. Would really like to ride to Rhinebeck, NY this weekend on the K4 (3hrs each way).

I am also considering changing the front wheel just in case it is a bearing issue I am feeling...

cheers
Andy

[Alan F.]

I am also considering changing the front wheel just in case it is a bearing issue I am feeling...

Hey why not?

[Johnie]

Andy, the thing about head bearings and adjusting them is that the pinch bolts on the lower tree need to be loosened before you adjust/tighten the steering head nut as your pushing the upper and lower tree closer with tightening the head-nut...I read that somewhere.
Don't forget to tighten fork pinch bolts when adj. done...!!

Spanner...trying to get my head straight about this. I tightened my steering head bearings on my K4 but only loosened the top fork pinch bolts and the center tree bolt. I am trying to figure out why I would need to loosen the lower fork pinch bolts too? Wouldn't the trees come closer together just by loosening the top pinch bolts. I mean, as you tighten the steering bearing bolt (not the big center triple tree bolt) that would pull the lower tree up with the shocks, correct? In other words, it would pull the 2 trees closer together which is what we are after, right? Of course if the lower bearing is already seated it would just pull the top bearing down into the race more. Or am I all washed up here...let me know

[Spanner 1]

No, your correct Jonnie, loosening the top pinch bolts achieves the very same thing.... just that the trees are free to pull closer together and not stopped by being 'fixed' by the forks..... so top or bottom works.!

[Johnie]

No, your correct Jonnie, loosening the top pinch bolts achieves the very same thing.... just that the trees are free to pull closer together and not stopped by being 'fixed' by the forks..... so top or bottom works.!

Thanks Spanner. I have to give mine another tweek. I saw another guy here have to do his like 5 times already.