Article [13] ST1300 - Maintenance - Front & Rear Wheel Install and Front Axle Animation

[jfheath]

I re-installed the front wheel a few days ago and checked the clearance as part of the procedure. Doing so brought this to mind again and reminded me that there is no adjustment available as the right-hand fork can't be moved laterally on the axle like the left-hand side can, so it started me wondering again.

I forgot to answer this particular point - but the answer is an interesting one. (I think so anyway).

The axle is drawn across to the right as the axle bolt is tightend, and because of the shoulder on the left hand end of the axle, tightening pulls everything together and clamps them tight all against the right hand fork leg.

The Caliper Bracket is clamped firmly on the right hand fork leg. It is fixed and cannot move.
The Axle is also clamped firmly against the right hand fork leg
The bearings are also clamped against the right hand fork leg. For the front wheel, it is the right hand bearing that is driven in first, so it is that one that rests firmly on the hub of the wheel.
That being the case the wheel is firmly clamped in position relative to the right hand fork leg and the right hand cliper bracket.

In theory, do everything correctly and that 0.7mm space is there automatically.

But it does rely on those wheel collars being put on the correct side and the correct way round.
It also relies to a smaller extent on the right bearing being driven in first. (I think it is not a coincidence that the bearing to go in first is the one that is on the side of the tightening axle nut).
And it relies on the person assembling doing things in the correct order.

That last point is possibly the stumbling block for some people.

Not many people have a hex (allen key) driver that will fit in the hex socket at the end of the axles. Yet that axle needs to be prevented from turning.
Not many people realise that tightenting the axle bolt isn't just holding the axle in place - it is providing a clamping force for the entire axle assembly.
A lot of people use the trick of using the fork leg pinch bolts to clamp the axle so that the bolt can be tightened.

So it is not beyong the bounds of possibility for someone to remember this trick and apply it to the right hand axle pinch bolts, rather than to the left. It saves going round the other side, after all. Which allows the axle bolt to be torqued up, but which then prevents the axle from being pulled across to the right. So the wheel is able to slide on its axle - or the axle is now too long, So the clearance will disappear on at least one side.

But worse than that, when the other pinch bolts are tightened and the clearance obtained, the forks will be splayed, and the weight that was held by the axle bolt is now taken up by the pinch bolts. And that axle bolt will work loose. Especially if you do the bit about bouncing the forks.

We've had at least one example on these forums where a bike has suddenly lost its axle bolt, and I reckon that this was the reason for it.

So its not just the securing - it is doing things in the right order that is critical.

The same applies at the back for a different reason. That required the stopper bolt to be secured before the axle. Otherwise it could lock in an angular / alignment difference between the bracket and the bolt, which will knock the caliper out of alignment.

 

[Andrew Shadow]

Gap in SMC through which disc passes has been taken from my original new bike replaced as a precaution at 36,000 miles. - 7.87 mm

I have no issues on the left-hand (SMC) side. There is plenty of clearance, so much so that I don't even bother to measure it as it is clearly visible.
The issue is between the right-hand (Brake lever) side brake disc outer face and the right-hand caliper bracket. Depending on where I measure it straddles between being just over 0.7mm and just under.

But it assumes that the model year is the same (yours is), and that discs and SMC are the same.

Mine is a 2009 as well. I don't know when it was manufactured. I have the same SMC as what is in your photo with the drain channel.

 

[Andrew Shadow]

The Caliper Bracket is clamped firmly on the right hand fork leg. It is fixed and cannot move.

Correct. The lateral position of the right-hand brake disc can not be altered relative to the caliper bracket either as the wheel is also clamped tightly against the right-hand fork leg.

A lot of people use the trick of using the fork leg pinch bolts to clamp the axle so that the bolt can be tightened.

I do have a 17mm Allan key and I do use it. As a matter of fact I do not tighten any of the pinch bolts on either side before I torque the axle bolt.

Barring some very strange and unusual defect such as the dimensions of the caliper bracket, or the fork leg mounting points for the caliper bracket, being out of spec somehow the only other explanation that I can see is something to do with the wheel bearings or their installation that is allowing the front wheel to be drawn to far to the right. When the time comes to replace the front wheel bearings I will have to pay extra attention to see if I can find something to explain this.

But it does rely on those wheel collars being put on the correct side and the correct way round.

They are in the correct position and orientation. I have checked and rechecked this so many times every time that I have the wheel off just to be sure that I am not screwing this up. While I do have two sets of wheels, and they both result in the same very low clearance, I only have one set of collars so that is a common point. I guess it is always possible that the right-hand collar is shorter than it should be. I don't recall ever seeing a specification for the length of the collars so I have never measured them. Using the dimensions of the collars that you have posted as a reference, the next time that I have the wheel off I will measure them and compare the results against your dimensions.

 

[jfheath]

I doubt if the wheel bearing installation will be the cause of what you are seeing. The total gap (inside + outside) would be the same no matter what the position of the wheel. I was just talking around the subject.

If your clearance is only just .7mm on both sides then that has to be to do with the size of the gap, compared to mine. But the same gap has to be present in that chrome retaining clip.

I'm not certain, but my recollection about my 06 was that the clearance was much closer than my present model. The R02 designation makes me wonder of they opened it out a bit - and new SMCs come with new retainer clips. I don't know about Canada, but we didn't have a change in model number between 2009 and the end of 2013. What I am wondering is if mine is a different spec from yours. Whatever 0.7mm both sides is within spec.
I reckon mine must have been amongst the very last A9s to have been built - it came off the production line in mid September 2013 - I bought it in Jan 2014 and it was discounted 'cos I reckon that they already had some 2014 models in store. Certainly a couple of weeks later, they had some blue ones in their showroom - which was one of the 2014 colours, not seen in the UK since the early ST1300s. I was miffed - cos I don't particularly like the red of my model.

 

[draser]

That required the stopper bolt to be secured before the axle. Otherwise it could lock in an angular / alignment difference between the bracket and the bolt,

During rear wheel securing process, there are no opposing forces that act upon the stopper bolt and the rear caliper bracket (that may perhaps cause twisting of caliper bracket and perhaps some caliper misalignment).
The caliper bracket alignment features are the flat surfaces resting against the inside of swingarm and wheel hub - that is the design position. How is securing the axle nut while holding the other end going to generate any force in caliper bracket against the stopper bolt, and in turn create a torsion momentum in the caliper bracket??

 

[Igofar]

It appears to me that some of you just keep questioning the instructions and measurements, and have stopped trying to figure out what has actually changed, or is actually causing the issues.
Your looking for the problems instead of the solutions.
Find the cause of the problem instead of throwing solutions at the problem etc.
Perhaps you should start searching for the cause, instead of questioning the cause.
People keep talking about the "set up", which side the spacers go, the gap, the way the forks move, etc.
We know all these things already, but what your searching for is why it is different for some reason.
Many things can cause these issues...
Were the bearings seated at the correct depth, or married too tightly against the inner wheel race (this will change a measurement)?
Are the dust seals over the bearings flattening out? (this will change a measurement)
Is the torque wrench used to tighten the axle correct, or has it been over tightening the axle, moving the bearing in too deep?
Is the end of the axle peened out and not sliding into the fork lower smoothly, pulling things out of measurement?
Is the hole in the end of the axle have a raised burr digging into the fork lower, dragging and pulling things out?
Are the wheel bearings OEM Honda, or have they ever been replaced with aftermarket cheaper bearings that may have different measurements?
Instead of fighting this with logic, trying to prove or disprove why it does not make any sense because the book measurements are such, take a step back, take a deep breath, and start really looking at things in detail, I'm sure you'll see something.

 

[jfheath]

It's just a general discussion Larry - arising from the fact that I seem have more available clearance than Andrew. I was suggesting ways in which it could possibly happen - but the bottom line is that nothing you can do will affect the total amount of clearance available. Only whether the disc is too close to one side or the other. There is a gap the disk has to pass through it with a certain clearance on each side.

The total gap that I have is about 7.6mm. 5mm of which is occupied by the brake disc. The disc sits quite centrally in that gap. But I don't remember the gap beign that large with my first 1300.


@draser


The stopper bolt has to be secured first so that the threads pull the head squarely against the boss on the swinging arm - and so that the peg square to the elongated hole int he caliper bracket.

If the axle bolt is tightened first, the stopper bolt can be sitting too low - so it has room to move/drop on untightened threads. Or- when the axle bolt is tightened, the caliper bracket tends to move round clockwise - which could pull an unsecured stopper bolt.

If the bolt isn't in place. a similar thing can happen. The hole isn't properly aligned, but the shaft of the bolt will go into the hole at a slight angle. It can be tightened - but it won't necessarily be tightening the flange of the bolt against the face of the boss on the swing arm. It will tighten against the threads when the bolt cannot straighten itself out any more.

So making sure that the stopper bolt is properly secured first ensure that the above cannot happen.

 

[draser]

Or- when the axle bolt is tightened, the caliper bracket tends to move round clockwise

Like stated in the post... the axle is held stationary and the nut is tightened.

the stopper bolt can be sitting too low

Not sure how... since it's snugged in its threads but not torqued to spec. From what I remember... it's a fine thread with minimal thread play, and when fully inserted until it stops (normal assembly practice) it'll present a parallel surface to the hole in the bracket.

I can see an "angle" happening if bolt is inserted afterwards, like you're stating, but even then if the bolt can be hand started and screwed in all the way w-out effort I don't see a problem.

I saw the manual... I guess it's written to prevent hand starting the bolt (2-3 threads in) then torquing the axle nut, then snugging up the stop bolt and then torquing... which doesn't make much sense... but it's worst case scenario.

To take this further, the issues with rear caliper bracket wear, or uneven wear I should say, simply comes from caliper not exercising equal forces on both sides, hence one pad works harder than the other... and guess what, that does create torque which moves one pad more than the other and pushes unequally against the locator clip in the bracket... and then we see the triangular wear in the recess where this clip resides. And why is the rear caliper going that... well, as seen numerous times on cars/motorcycles, where one pad is thinner than the other, the lack of maintenance of the caliper sliding pin(s) and pistons/seals determine the "floating" caliper to not float/self adjust anymore.
Also, caliper design robustness is responsible for some of that, they should have used the 2-pin locator system for the pads just like the fronts are, but... since the rear braking is only say.. 20% of the total braking force, it's passable.

 

[Andrew Shadow]

...... take a step back, take a deep breath, and start really looking at things in detail, I'm sure you'll see something.

I have, every time that I put the wheel on and I have never found anything that appears wrong.

I can confirm that the wheel bearings are Honda OEM bearings, so OEM in fact that they are still the original ones installed by Honda at the factory. I don't intend to remove them solely to investigate this so determining whether or not Honda installed them correctly will wait until they need to be replaced. As stated earlier, I get the same result with my spare wheel so both wheels would have to have their bearings installed in the same defective manner to the same degree, which would be quite the coincidence.

Beyond that none, not one, of the other items that you have suggested as a potential cause are present unfortunately. I wish one of them were so I would know the cause, so if you have any other hunches I'm happy to check them.

Unlike the left-hand SMC side where the position of the caliper bracket and brake disc can be changed relative to each other, this is not the case with the right-hand side. The right-hand side caliper bracket and brake disc are clamped in a fixed position relative to each other, and this can't be altered. Many of the items that can influence this clearance Honda does not provide dimensions for.

 

[Sidekick]

Are the dust seals over the bearings flattening out? (this will change a measurement)

I am wondering about this. By design, dust seals are passive components, and I don’t see how they could influence the position of the front wheel on the axle. The collars are designed with 10 mm shoulders that sit directly on the bearings' inner races, ensuring a metal-to-metal contact. The dust seals are constrained within this space but don’t play any role in the torque sequence or alignment process.
Am I missing something?

 

[jfheath]

The collars are designed with 10 mm shoulders that sit directly on the bearings' inner races, ensuring a metal-to-metal contact.

I think the issue arises when the collars, sides, orientations are mixed up. To many of us there is ony one way. To someone who doesn't know/doesn't check/makes a mistake - there are 8 different ways that you can attempt to fit those collars. Only one is correct.

The issue that Larry describes can arise with the collar that is intended to fit on the left hand side. This has a 10mm shoulder and a 4.1mm shoulder. The 10mm shoulder always fits into the bearing. But if that is put in the wrong way round on the left or on the right hand side, then tightening the axle will clamp that flange directly onto the bearing seal, squashing it by 60%. Once squashed it doesn't bounce back - so subsequent fitting of the correct colalr is going to be hampered by a severly flattedned seal. Which I think is what Larry was suggesting might be the cause of loss of clearance.

And lets face it - when you look at that 4.1mm side (see pic) - somehow, although it is correct, it looks to be really odd. It looks too small - because when fitted the axle shoulder buts up against it and makes it look longer than 4mm. So I guess people think it should be turned round the other way.

And if anyone is capable of making that mistake, they are also capable of trying to fit the same collar onto the right hand side.

In fact all of this discussion has come about because I commented that I had "oodles of clearance" on both sides of the disk. Mine is roughly even at 1.33 and 1.24mm. Significantly more than 0.7mm. Nearly twice. I don't know how that compares to the other bike - I just know that the other is within the 0.7mm spec. The 'problem' may come down to my use of the word 'Oodles'.

 

[W0QNX]

First is it possible confusion is arising from John Heath saying he has 1.33mm and 1.24mm ON THE LEFT SMC SIDE and Andrew saying his RIGHT SIDE is only .7mm?

The left side (SMC) can be changed by moving the fork on the axle but the right side (non SMC) is fixed and ends up where the manufactured parts fasten together. Those part thickness's will vary with manufacturing part tolerances resulting in clearance variations so Honda sets .7mm as the minimum clearance allowed.

@Andrew Shadow my RIGHT SIDE NON SMC SIDE has a measurement of .047" or 1.19mm. That is the thickness of feeler gauges that I can lightly force in under at the closest point of the caliper bracket to the disc. It does "give" a bit when inserted so true clearance would be a bit less maybe .040" or 1mm. I can't "feel" the true clearance so a light forced measurement was done. This clearance IS AFFECTED by the thickness of the brake disc. Mine is near new (just replaced) at 4.95mm thick. As the disc wears clearance will increase. I was serious earlier when I said my 4.1mm worn disc would give you more clearance.

This is one of those cases of where if it works the day you got the bike it should only get better as it wears down. I don't think it is even something a person would ever check (unless you crunch the bike) unless he is making parts changes to the brake system. I think half the Honda spec of .7mm minimum would still work as clearance is clearance and these parts don't move in use.

Short version, my bracket to disc clearance on the right side is 1mm.

 

[Andrew Shadow]

I don't think it is even something a person would ever check (unless you crunch the bike) unless he is making parts changes to the brake system.

I check it every time that I install the front wheel as indicated in the service manual.
I didn't measure my discs. They are still the original ones and unless they were manufactured to thick they shouldn't be an influence.

Short version, my bracket to disc clearance on the right side is 1mm.

I am measuring in inches because I don't have metric feeler gauges. 0.7mm is 0.28". On the right-hand side between the brake disc outer face and the brake the largest clearance that I have is 0.030". At one spot particular spot only I have about 0.025"- hard to measure. I do have clearance however and there is nothing touching anywhere and I have no brake performance problems of any kind and there is no symptoms of any negative impact on the brake performance so for now I use it as it is. Maybe when the time comes to replace the wheel bearing I will find something. I just have always wondered why it is so tight on the one side. There is plenty of room, oodles in fact, for the disc to be moved way over to the left and be much more centered in the caliper. I no longer know anyone with an ST1300 that I can use to compare parts with to see if something on mine is different that would shift everything to the right so I am left curious about it.

 

[jfheath]

I'll get out and measure my right hand side. I hadn't considered that that may be the difference ! Is yours a 2009 purchased ST1300 ?

Ok - that is broadly similar. I just put 4 gauges together, trapped them in the holder and they slid through the gap with a slight drag - 0.30, 0.28, 0.33, 0.38 = 1.29mm
One was easier than the other three. And by far the easiest to measure was the inner side of the disk viewed from the other side - so eg the right hand caliper, inner disk surface, viewed from the left hand side through the spokes. You can get a good idea of the angle to use and pushing it slightly up towards the edge of the brake disk, you can see the gauges emerge at the other side. (Although it only has to go through the start of the slot - its good to know it is clear all the way through.). On the outer side of the disk, the view is obscured.

 

[Andrew Shadow]

Is yours a 2009 purchased ST1300 ?

It is a 2009 model year that I purchased at the end of December of 2011.
The serial number label affixed to the head-stock states 12/08. I have always assumed that this meant that it was manufactured in December of 2008.

 

[jfheath]

We don't have anything like that on the headstock - just the VIN. I only know the date of production because of mine because I was buying a brand new bike in Dec 2013. It was discounted. I wanted to know that it hadn't been sat around in the showroom for 4 years. Or salvaged from the aftermath of the Tsunami. Then he started giving incorrect facts about it to convince me. So I started backing off from the sale. He got onto Honda and they sent me a copy of the production slip.