Hi All,

I'm currently stripping down/rebuilding a CBR400 NC23. The steering on the bike felt a bit notchy, it settled in the centre and there was a bit of resistance steering left-right from the centre.

So, when it came to taking the triple tree off, I expected to find some indents in the ball races where the bearings had worn them away - causing the unusual steering, but they weren't bad at all. Also, the bearings themselves seem to be pretty healthy (I'll replace them still, obviously). So, I'm at a bit of a loss as to what's causing it?

Perhaps its just the way it feels with no handlebars/forks/front wheel attached? Perhaps NC23's are 'all like that, sir'?

Is anyone able to cast any light on this? Also, do you know if I can change by bottom ball-race? It seems to be very well fixed to the stem and I can't work out how to remove it.

Thanks in advance,
Ryan.

does it have a steering damper on it? was the top nut on the yoke too tight? was there crap and dirt in the bearings?

if its notchy with the wheel on the floor id say the head race bearings

Change the bearings anyway, they're cheap and easier with the bike apart.

Bottom bearings are more difficult to get off the stem but you can use a screwdriver to start it off. Tap it into the rubber seal and as it goes in work it until the bearing moves. It will probably break apart, once it moves work the other side so it doesn't bind, then use a drift. It's not a subtle proceedure, I use a small hammer for the screwdriver and 1/2 pound hammer for the rest.
Some hondas need a tool to start the races moving - dril a piece of angle steel and put a bolt in, then use the bolt on the lip of the race, if you don't have a long drift then get an old rear axle or gearbox mounting bolt, put the nut on the end so you don't kill the thread.



Ues the old races to drift in the new ones. I use engine paint and "PU Laquer" (get it from Halfords) for the tipple clamps



Remember to get the grease into the bearings before it all goes back together

Simon_Ed wrote:does it have a steering damper on it? was the top nut on the yoke too tight? was there crap and dirt in the bearings?

if its notchy with the wheel on the floor id say the head race bearings

Yeah, there was quite a bit of crap in there and the top nut may have been a bit too tight (had to use an impact driver to get it off)...I'll clean it all up and put some new bearings in and see what it's like.

Thanks for your help.

Evilchicken0 wrote:Change the bearings anyway, they're cheap and easier with the bike apart.

Bottom bearings are more difficult to get off the stem but you can use a screwdriver to start it off. Tap it into the rubber seal and as it goes in work it until the bearing moves. It will probably break apart, once it moves work the other side so it doesn't bind, then use a drift. It's not a subtle proceedure, I use a small hammer for the screwdriver and 1/2 pound hammer for the rest.
Some hondas need a tool to start the races moving - dril a piece of angle steel and put a bolt in, then use the bolt on the lip of the race, if you don't have a long drift then get an old rear axle or gearbox mounting bolt, put the nut on the end so you don't kill the thread.



Ues the old races to drift in the new ones. I use engine paint and "PU Laquer" (get it from Halfords) for the tipple clamps



Remember to get the grease into the bearings before it all goes back together

Brilliant! Thanks for this. I'll give that a go.

Ny old NC29 had notchy steering on its MOT - hence it failed!

It was at the straight ahead point of the bars - does that make sense. So I never noticed it.

But they tweeked it up ( a smidge he said ) and it went away. So it passed!

He said sometimes they just fix themselves with a small tighten?

Notchy stealing usually means the head race bearings are gone on the way out, Yes this will fail or have an advisory on the MOT.
Evil has posted how to change them.. Did mine in an hour on my own.

Definitely change everything with fresh,
it is a brute force and ignorance kind of job but straightforward enough.

It's amazing what seems a tiny surface defect feels like at the bars, especially if its all too tight, I set it a little loose before doing the topnut.

For MOT failures a quick fix can be a quick strip and packing with loads of grease l, or just slackening it off a bit :)


As a sidenote lookup the torque value on that topnut, on my rc24 its about 134nm!!!