Kawasaki Concours Forum

The C-14, aka Kawasaki Concours-14, the new one :) => The Bike - C14/GTR 1400 => Topic started by: roadie on September 21, 2011, 01:40:53 PM

Title: Loose steering stem top center bolt symptom
Post by: roadie on September 21, 2011, 01:40:53 PM
While riding home last night I noticed a single knock when I engaged the front break (stopping at red light slow speed), and another knock when I disengaged the front break.  Its almost a two-step knock.  All coming from somewhere in the fork area. Is this potentially a loose steering stem top center bolt issue or some other possibilities?  thoughts?  Haven't had time to check it yet but would value any insight anyone might have.  i'm on an '09 ABS.
Title: Re: Loose steering stem top center bolt symptom
Post by: B.D.F. on September 21, 2011, 02:04:11 PM
Most likely, yes. We have seen quite a lot of that on C-14s, and with very few miles on them- mine started to 'clank' with less than 3K miles on it.

The bearings are adequate but seem to be a little on the weak side. Also, I think a bike this big needs a little more damping on the steering stem than provided by the O.E.M. angular contact ball bearings. I changed mine somewhere around 50K (I think) to tapered roller bearings and they have proven to require a lot less adjusting, provide more damping and I have not noticed any change in the turn- in speed or any other handling degradation. Changing them is a bit painful and requires a small bucket of bad words but it is worth it in the end IMO. By the way, my dealer offered to change the bearings on my bike under warranty but I still chose tapered roller bearings although I had to provide the labor and actually buy the bearings.... and it was still the better way to go.

Brian


While riding home last night I noticed a single knock when I engaged the front break (stopping at red light slow speed), and another knock when I disengaged the front break.  Its almost a two-step knock.  All coming from somewhere in the fork area. Is this potentially a loose steering stem top center bolt issue or some other possibilities?  thoughts?  Haven't had time to check it yet but would value any insight anyone might have.  i'm on an '09 ABS.
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on September 21, 2011, 03:04:29 PM
Thanks Brian...as an initial course, do I just need to check that it is at the correct torque spec?
Title: Re: Loose steering stem top center bolt symptom
Post by: B.D.F. on September 21, 2011, 03:12:45 PM
Usually, yes. Snugging the bearings always seems to take the knock out of the front end. Eventually it does not work for a slight weave that the bike picks up in the 40 MPH range.

Just to expand on this a little bit: the original bearings are angular contact ball bearings. The two races oppose the ball bearings at an angle and it takes two bearings to make one working bearing (or bearing assembly). Unfortunately the angle is shallow and as the bearings wear (pound out actually) the contact angle gets closer and closer to the axis of the steering stem itself. What eventually happens is that all the force between the bearings is <virtually> in-line with the stem axis and while it is perfectly safe and the bearings still work, they can no longer exert any side pressure and therefore cannot create any damping for the steering stem. Even if tightened far beyond spec. they just do not resist the front end from turning enough to absorb the minor, low- speed wobble. It is not dangerous (a low speed wobble is NOT the same as a high speed wobble) but it can be annoying.

Brian


Thanks Brian...as an initial course, do I just need to check that it is at the correct torque spec?
Title: Re: Loose steering stem top center bolt symptom
Post by: VirginiaJim on September 21, 2011, 03:16:33 PM
It is not dangerous (a low speed wobble is NOT the same as a high speed wobble) but it can be annoying.

Brian

Unless, of course, you are a Weebl.
Title: Re: Loose steering stem top center bolt symptom
Post by: lt1 on September 21, 2011, 03:42:01 PM
Unless, of course, you are a Weebl.
Actually, it is more dangerous if you are not a Weeble.  Motorcyclists can fall down.
 
Weebles 


(wait for it)


wobble, but they don't fall down.
Title: Re: Loose steering stem top center bolt symptom
Post by: VirginiaJim on September 21, 2011, 03:43:22 PM
Ya got me....  :rotflmao:
Title: Re: Loose steering stem top center bolt symptom
Post by: Wild_Bill on September 22, 2011, 12:51:12 PM
Check your front brake pads.
Mine started to make a slight clunk when stopping and progressed to a squeal and shudder.
One of the pads material was as thin as a piece of paper.

My bike has only 15,500 mile on it.

Bill
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on September 22, 2011, 05:17:00 PM
Yeah still got 3mm of tread. Imma check the torque on the stem on Sunday.
Title: Re: Loose steering stem top center bolt symptom
Post by: HndaTch627 on September 26, 2011, 10:44:00 PM
I had both, the bearings were loose and the top triple tree nut had backed off as well.  Mentioned it when i took my bike in to have the tire pressure sensors replaced and the tech's answer was "yeah, we've seen a good deal of that".

Was not exactly the response i had expected.
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on September 28, 2011, 12:41:50 PM
so closed issue (for now)...I torqued it to specs and no more double knock.  thanks for all the input.
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on September 28, 2011, 12:43:30 PM
PS:  I f'ing love this bike!
Title: Re: Loose steering stem top center bolt symptom
Post by: julianm on October 01, 2011, 11:15:27 AM
so closed issue (for now)...I torqued it to specs and no more double knock.  thanks for all the input.

I think I have a similar problem. Could you please advise  exactly what you tightened and the torque specs. you used.. A pic would be appreciated . (On the old forum there was a sticky with a lot of torque specs. but couldn't find it on the new one )
Many thanks
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on October 01, 2011, 11:23:26 AM
Remove the little black plastic cap on stem right between your handlebars. U'll need an Allen socket, extension, and torque wrench. Tighten to 79.7 foot pound. I might be off by a tenth. Will check my manual tonight an correct.
Title: Re: Loose steering stem top center bolt symptom
Post by: Gsun on October 01, 2011, 12:02:59 PM
I think I have a similar problem. Could you please advise  exactly what you tightened and the torque specs. you used.. A pic would be appreciated . (On the old forum there was a sticky with a lot of torque specs. but couldn't find it on the new one )
Many thanks

Here is the torque specs in the C-14 area.

http://www.zggtr.org/index.php?topic=1652.0 (http://www.zggtr.org/index.php?topic=1652.0)

Here is what the manual says:

○Tighten the steering stem nut with 55 N·m (5.6 kgf·m, 41
ft·lb) of torque first, and loosen it a fraction of a turn until
it turns lightly. Afterward tighten it again with specified
torque using a steering stem nut wrench [A].
Special Tool - Steering Stem Nut Wrench: 57001-1100
Torque - Steering Stem Nut: 23 N·m (2.3 kgf·m, 17 ft·lb
Title: Re: Loose steering stem top center bolt symptom
Post by: VirginiaJim on October 01, 2011, 01:44:21 PM
I think the next time I'm doing mine is that I'll increase it to 19lbs and see how it feels with that.  I did the 17lbs and it still had the clunk occasionally.
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on October 01, 2011, 02:04:21 PM
The steering stem nut?  I'm almost positive it gets tightened to 79 ft pound not 17. I'm on a 2009. 
Title: Re: Loose steering stem top center bolt symptom
Post by: Jeremy Mitchell on October 01, 2011, 02:11:24 PM
The steering stem nut?  I'm almost positive it gets tightened to 79 ft pound not 17. I'm on a 2009.

You are both correct are correct.  On page 2-11 of the manual it states 79 lb ft for the steering stem head bolt.

The steering stem nut is torqued to 17 lb ft.
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on October 01, 2011, 02:28:56 PM
Thx, yeah I only Tightened the head bolt. That's what cured my ish.
Title: Re: Loose steering stem top center bolt symptom
Post by: VirginiaJim on October 01, 2011, 02:41:28 PM
They all work together...
Title: Re: Loose steering stem top center bolt symptom
Post by: roadie on October 01, 2011, 03:30:26 PM
understood.  I didn't get that deep into the stem...just started with top center bolt...seemed to do the trick for me.  When I hit my 15,000 mile mark in the coming weeks, its on my list of things to check.  Guess i need to buy the special wrench for tightening the nut?  Where did you get?
Title: Re: Loose steering stem top center bolt symptom
Post by: VirginiaJim on October 01, 2011, 03:39:59 PM
ehcycledude@yahoo.com  is the one that makes them.
Title: Re: Loose steering stem top center bolt symptom
Post by: DenverC-14 on October 02, 2011, 08:51:33 PM
I think I'm having similar issues, but wanted to get some input before moving forward. I've experienced a pretty substantial head shake/weave thing going on in high speed cornering. It was really bad the last ride on corners I'm very familiar with and have had no issues in the past on I've also noticed the "thunk" going over train tracks and sometimes when applying or releasing the front brake. Thoughts?
Bike is an '08 non abs with 28k miles. Last major service done at dealer at 17.5k
Title: Re: Loose steering stem top center bolt symptom
Post by: julianm on October 05, 2011, 01:15:17 PM
Here is the torque specs in the C-14 area.

http://www.zggtr.org/index.php?topic=1652.0 (http://www.zggtr.org/index.php?topic=1652.0)

Here is what the manual says:

○Tighten the steering stem nut with 55 N·m (5.6 kgf·m, 41
ft·lb) of torque first, and loosen it a fraction of a turn until
it turns lightly. Afterward tighten it again with specified
torque using a steering stem nut wrench [A].
Special Tool - Steering Stem Nut Wrench: 57001-1100
Torque - Steering Stem Nut: 23 N·m (2.3 kgf·m, 17 ft·lb

Thanks to you and Roadie for your replies