Headshake & "Loose" Head Bearings

[XmisterIS]

Firstly, I say "loose", but actually the head bearings are as tight as haynes says they should be.

Anyway, I had the head bearings replaced at the last service because the old ones were knackered, and ever since it's felt like the forks are too "loose", if you get what I mean. Before, there was quite a bit of resistance - more than Haynes said there should be, and I actually quite liked that!

Also, since the head bearings have been replaced, I've noticed a bit of headshake under hard acceleration at high speed. (When I say high speed, I mean over 90mph, on a private road )

It doesn't feel out of balance, just shakes a little. In fairness, the mechanic said, "be careful, it will feel a lot different". I'd like the stiffness back again though.

Would it be bad for the head bearings if I tighten them up more? Or would I benefit best from a steering damper? (goodness knows where I'll fit it on a naked SV!).

[megawatt]

Lift the front of bike off the ground, hold the very bottom of both fork legs and try to pull and push them forwards and backwards. If you feel any movement or clicking, tighten the headstock nut a little and try again.

[eastanglianbiker]

dont forget its the nut under the top yoke that needs to be adjusted correctly not the one on top of the yoke

[XmisterIS]

Ok, will do. I've ordered an adjustable C-spanner for future use too, seeing as it was only £10, I thought why not.

[megawatt]

Two C spanners are ideal. There is a castellated adjuster nut and sometimes a locknut. Very often, just an adjuster nut , then top yoke and then top yoke domed nut.

[Colin the Bear]

Don't tighten the head bearings to give you a stiffer feel. If they are so tight you will get premature failure. Front wheel off the ground in a stable position and adjust the setup till there's no lateral play, but free movement in a rotary motion. Check for a notchy feel at this time.

There's another thread about head shake. It can be caused by something as simple as wrong tyre pressure or uneven tyre wear.

If you need stiffer steering , a damper is the way to go imo

[Jixerman]

Don't tighten the head bearings to give you a stiffer feel. If they are so tight you will get premature failure. Front wheel off the ground in a stable position and adjust the setup till there's no lateral play, but free movement in a rotary motion. Check for a notchy feel at this time.

There's another thread about head shake. It can be caused by something as simple as wrong tyre pressure or uneven tyre wear.

If you need stiffer steering , a damper is the way to go imo

 

CB13's suffer with this and and Mr Bear has said (on CB13's at least) its generally down to mismatched tyres or uneven wear on the front tyre due to braking heavily

My tyre tread is stepped but still legal and probably caused by excessive braking by previous

If I let go of the bars between 30&50 the steering wobbles....badly . It supposedly does it at higher speeds but I ain't brave or stupid enough to test it

I'm going to get as much out of the front tyre as poss before replacing it so no riding handsfree for me at the mo

Incidentally I have Bridgies which are going to be replaced with Michy Pilots when the time comes

[Tango]

Did the mechanic fit tapered head bearings? if it had plain ball bearings before and now has tapered bearings it will feel quite different......so it may be more of a case of you adjusting to it rather than adjusting the bike to how it used to feel.....

[XmisterIS]

Did the mechanic fit tapered head bearings? if it had plain ball bearings before and now has tapered bearings it will feel quite different......so it may be more of a case of you adjusting to it rather than adjusting the bike to how it used to feel.....

 

what is the difference? That could be the reason then - I popped the bike up on the abba stand yesterday eve and there is no play in the forks at all.

Also, I played around to see where the shake happens, and I found that when I cane the crap out of it from 85mph (on a private road) upwards, it shakes under acceleration, but then smooths out when I stop accelerating. I wonder if that's just the bike saying "she cannae take nae mere, cap'n". It is an SV after all and they tend not to like going super-fast (they top out at 125mph, I think).

[Colin the Bear]

Under acceleration the weight shifts to the back wheel making the front light. An extreme case of this would be a wheelie. The front is then hop, skip and jumping along the road reacting to all the little undulations and anomalies. There seems to be nothing wrong with the front end so either a damper or ease off the throttle tiger

[Stu]

Also, I played around to see where the shake happens, and I found that when I cane the crap out of it from 85mph (on a private road) upwards, it shakes under acceleration, but then smooths out when I stop accelerating. I wonder if that's just the bike saying "she cannae take nae mere, cap'n". It is an SV after all and they tend not to like going super-fast (they top out at 125mph, I think).

 

I will put money on suspension set up and not the bearings or tyres

The SV suspension is just too soft and I don't think you can adjust it much on them

[XmisterIS]

Also, I played around to see where the shake happens, and I found that when I cane the crap out of it from 85mph (on a private road) upwards, it shakes under acceleration, but then smooths out when I stop accelerating. I wonder if that's just the bike saying "she cannae take nae mere, cap'n". It is an SV after all and they tend not to like going super-fast (they top out at 125mph, I think).

 

I will put money on suspension set up and not the bearings or tyres

The SV suspension is just too soft and I don't think you can adjust it much on them

 

the forks are a soft as hell ... that seems to be a well-known problem with them. you can do a GSXR fork swap, but I think I'd rather sell the SV when the time comes and buy another bike!