Tyre balance?

[Mr Gazza]

Studying this picture of rbt1548's lovely M900Sie, I notice that the red spot is apparently randomly positioned on the rim and that there is a balance weight approx. 90 degrees round from it.



This is in no any criticism of Robert's bike, but shouldn't the red spot be placed near the valve? I though it marked the lightest point of the tyre and so putting it near the valve assists in balance?
Both my new Angels have the red spot on the valve and also further weights, which on the front are also near the valve. (not so the rear.)
I seem to be needing more weight to balance with the new ones.. Are they getting sloppy with the evenness of construction these days?

[Luddite]

A good spot, Mr Gazza. I reckon if you'd been around in WWII, you'd have been scanning aerial photos for U-boat pens and the like!

I think you're right though, the red dot indicates the lightest point on the tyre and so lining it up with the valve should minimize the number of wheel weights needed to achieve balance. It's also a useful reference point to indicate if the tyre has slipped on the rim at all. Unlikely on the road but perhaps a possibility if you did a lot of track days on your Panigale V4R.

As far as quality control goes, my last three tyres (Monster and Gilera) have actually needed fewer weights with each new tyre so I think it's just a bit of a lucky dip.

[Mr Gazza]

[QUOTE=Luddite;565287]A good spot, Mr Gazza./QUOTE]

I see what you did there...

Yes I sure would have been on the case with the aerial imagery analysis. I have been very interested in Aerial Archaeology for some time. I was flying models carrying wet film cameras with servo operated shutters long before it became easy with drones, digital cameras and live viewing.. You can even do it in an armchair these days, with Google Earth.
I have spent hours in the local museum, where I can request aerial survey photos of specific grid squares from their archives.
It's wonderful being allowed to handle (cotton gloves are provided) the actual photos taken from Canberras that I saw flying in their day. They took 12" square plates which were trimmed down to 9" photos to eliminate lens parallax. most still have the cartographer's pin holes in them at strategic points like road junctions and so forth.
As the cameras rolled, they flew at the correct speed and height for each exposure to overlap perfectly... Which they do. What is even more amazing is that frames from years apart match perfectly... that's some pretty skilled flying.

WW11 PR pilots are my heroes, they had the fastest planes and no guns.

Did you know that you had one of my Headlamp adapter rings in your avatar?
One of the last jobs Buzzbomb did on his 1100 Monster was to convert to an early Monster headlamp and fit one of my rings (He called me Lord of the Rings sometimes, and other unprintable things!).
As a nod to me he had them put a ring on the logo for the weekender... His legacy lives on..

[rbt1548]

As it's my bike that's being discussed I thought I'd contribute to the thread.

Let me assure you no offence has been taken at all in your pointing out positioning of the red dot on the tyres. The tyres have only a few hundred miles on them and were fitted prior me getting the bike.

As far as the positioning goes I am now not convinced it really matters, others will have their own opinions, and I used to believe the same that the dot was crucial.
However I have had 5-6 pairs of tyres fitted, to various bikes over the years by the conscientious guy in a small local bike shop, after the first fitting I queried that he had not balanced the tyres, he said he would if I wanted but he doesn't usually balance tyres unless specifically asked to do so.
The guy builds engines for TT racers and helps out in the pits during the TT, ( not for one of the bigger teams but to help financially strapped riders out), he stated that if they are changing tyres at the races they don't balance them, partially because of the improvements in tyre technology, and partially because the riders can't really tell the difference, obviously some riders insist that they are balanced to the Nth degree, while, as mentioned, some won't notice if they're not balanced. His premise was if riders going at those speeds at the TT can't tell the difference, would a normal wee guy on the road notice?

I understand that we are all different, and there is certainly no reason why people shouldn't request that they are balanced, I was only putting my slant on it as to why I wasn't that bothered, and to be honest I haven't noticed any out of the normal vibrations etc., when out on the bike, (yet!!!)

What I did notice was, that there are no tyre creep securing bolts on my wheel on the Monster, I had them on my Commandos to help with the power coming from the rear wheel

To get back to the Red Dot positioning, manufacturers must produce multitudes of tyres every day, surely they can't balance every tyre before putting the dot in the correct position, is it done automatically by positioning in the mould, or is it sneakily done randomly?

[Luddite]

Originally Posted by Mr Gazza

Did you know that you had one of my Headlamp adapter rings in your avatar?

I can see it now you've pointed it out - a nice touch! Of course, I've got Geoff's old panels on my Monster so, in a way, there's always a part of him riding with me.

Like you, I find aerial photography fascinating although I've had no actual experience of it, I just find the results and the procedures really interesting. I believe last year was really good for aerial archaeology due to the really dry summer revealing the outlines of all sorts of hidden gems.

Those WWII PR pilots were certainly a breed apart - I love those PR Spitfires in blue (or even pink). Real thoroughbreds - as you say, usually no armament but capable of over 440mph and flying at over 40,000ft - very special.

I'm sure digital photography has transformed aerial surveillance - I remember reading about the early US spy satellites that used wet film. They had to jettison the exposed negatives back to earth in a small capsule that was caught in mid-air by a specially equipped plane - very ingenious!

[mickj]

None of the tyre fitters around here balance rear tyres unless specifically asked to. They all say it does not make any difference as by the time you have attached drive sprockets and chains they will be out of balance again.

[Mr Gazza]

Thank you for jumping in Robert. I hope you don't mind me stealing your picture from your Bellypan sale thread... I didn't want to hijack that.

Interesting comments re balancing, I'm not sure that I'm brave enough to omit the balancing even if I could feel no difference, I would worry that the constant tremors would be wearing the suspension parts.
I didn't always balance my wheels when I fitted my own tubed tyres to my oldies. It used to be said that it wasn't worth it on rear wheels anyway because of the chain thrashing round there. I would static balance front wheels if the bearings were good enough.

As for the security bolt, I have always ditched them when possible. T140's were fitted with two as standard and if building with new rims, would insist that they were not drilled for the bolts... Something I did with my Commando's new rims earlier this year. The tyre can only slip if the pressure is stupidly low, which is why they fit security bolts to trail bikes running very low pressures for mud plugging. The danger is that it will rip the valve out if the tyre pulls the tube round, this is not possible with a tubeless tyre.

I also wonder how accurate the red spots are, but it's something that could be, and probably is, an automated operation for each tyre. Strange that the balance weights don't always seem to have any relationship with the spot or the valve though?
I have (I think) 43 grams near the valve and red spot, which seem a lot and is clearly all down to the tyre, as weights have not appeared there before.

New tyres are not always round either, and this is bound to lead to some patter and poor wear in extreme cases.
I seriously considered making a tyre lathe a couple of years ago, to re-profile the flat off my rear tyre. It has already been invented and it is claimed that a far superior ride quality and wear is had if a (car) tyre is skimmed flat and round from new or worn. They do exist for bike tyres, but it's a bit more involved as the tread is not flat like a car's. Each tyre has it's own profile, but I was on the case with a virtual invention involving a router and a profile following jig.... Some ideas are just too out there to manifest!!

[Mr Gazza]

Originally Posted by Luddite

I've got Geoff's old panels on my Monster so, in a way, there's always a part of him riding with me.

Many of us now cherish bits and pieces that perpetuate Geoff's memory... What a remarkable man to have deeply touched so many club folk. Moco1961 and I are secretly plotting to commemorate Geoff each year with an idea that you first suggested in that fateful "Buzzbomb" thread.

I was lucky enough to get up close to the BBMF's blue PR Spitfire last year on our club visit to RAF Coningsby.
Squadron Leader Mark Discombe talked us through each of the Spitfires and Hurricanes and when asked which was his favourite, he said it's like having a favourite child.. You shouldn't have one, they are all different and excel in their own way. But when we got to the PR, there was a different tone and glint in his eye. This was the plane he flew regularly, a late mark with some lovely touches, like a retractable tail wheel.
He was able to stash his travel bag in the redundant camera compartment and use it as a sports tourer Spit' when he was doing the show rounds. The fastest of the Spitfires in the collection, Disco described how it bucked and fought when trying to form up with the slower planes.. She just wants to GO he said. As he spoke he had a way of taking me into the cockpit with him that made all the hair stand up on the back of my neck...Wonderful, what a privilege!

I'll see if I can find a picture of the Flying Boxcar that caught the returning satellites by the parachute lines. It had two huge booms with a wire between that hooked the lines up!! When they winched the first one in, the chappie who grabbed it to pull it in was surprised to find it was still quite hot from the re-entry!

[Mr Gazza]

Howzat?

[Flip]

After leaving school I was a tyre fitter for many years and during the years fitted pretty much every type of type of tyre from private car of course through to commercial trucks (both split rim and tubless/super singles etc.), fork lift trucks, agricultural and one we're all interested in here- motorcycle for both race (hand cut slicks -remember those? I also re-grooved truck tyres for those loving the rubber smell) and road.

Admittedly things have changed quite a lot through manufacturing and quality control etc.

But yes the simple answer is the coloured dot indicates a light spot in the tyre construction and ideally should be placed by the valve if the fitter knows (you'd be surprised how many don't) or can be bothered.

However, just to confuse things, sometimes there would be two coloured dots and as I always understood it, a yellow dot indicated the light spot of the tyre and if the fitter knew/could be bothered this is the one that should be placed by the valve.

Along with the yellow dot there would also be a red dot which indicated the radial run-out -tyres were never quite perfectly round and as nor were (are?) wheels so they too would be marked with an indent to line this red dot up to equal things out as much as possible. This point in the tyre was (and possibly is still) less known about - try asking a fitter and see what they say.

There are a lot of factors to be taken into account when balancing wheels such as, (the already mentioned) sprocket carrier and brake discs which will all contribute to a frequency vibration at a given speed.

Personally I balance mine myself wheels fitted into the bike with the discs but calipers removed for the front, the rear is trickier as to use the same method the chain also needs to be removed.

Of course this is really only a static balance as opposed to a dynamic process using a machine but I have never suffered any wobbles on road or race bikes.

https://www.google.co.uk/url?sa=t&rc...ZBI6vQP3OVv2BG

[rbt1548]

Originally Posted by Mr Gazza

Thank you for jumping in Robert. I hope you don't mind me stealing your picture from your Bellypan sale thread... I didn't want to hijack that.

No problem at all Mr Gazza!

I suppose the, "I balance, I don't balance" debate could end up an oil thread, I just think it's each to their own. As for me, if a tyre fitter had balanced them I would be quite happy, by the same token, going by various opinions, I now wouldn't be too bothered if they weren't, (unless I'd paid for them to be of course!), and just to throw a spanner into the works,..... what about Dyna Beads??????

[Luddite]

Originally Posted by Mr Gazza

Howzat?

Howzat indeed!

I wonder if England's cricketers will be able to catch as well!

[utopia]

I'm fussy about my tyre balance, but that's more because I can be, rather than that I think I need to be.
This has come about since I started to fit my own tyres .. which began when I was skint and fitted a pair of ex-desmodue race scrubs and has continued since I fitted carbon wheels (which I'm not letting a tyre fitter anywhere near).
I use the cable tie method .. and I can report that it works very well indeed on original, 3-spoke monster wheels (later type) and also on my Dymag carbons.
I utilise nothing more brutal than a couple of 3 inch long, plastic, bicycle tyre levers to ease the tyre onto the rim, and even these are not strictly necessary .. I've done it with just my thumbs in the past.
The reason I mention all this is that, even after removing the cable ties, its fairly easy to rotate the tyre on the wheel before seating the beads.
I therefore first balance the bare wheels alone (without tyres but including sprocket and discs) and mark the heavy point ... which does not necessarily correspond to the valve position) before fitting the tyre with the marked light spot aligned with the measured heavy spot on the wheels.
I then static balance the wheel/tyre assembly before seating the beads.
Because the tyre beads are not yet seated on the rim, I can then rotate the tyre on the rim until the most favourable position is found .. ie the nearest to balance without any added lead.
Thus the lead needed is kept to a minimum.

Ok, some might say that the above is being over-fussy .. but its not hard to do, so why wouldn't you ?
Similarly, I don't know exactly how important wheel balance is on a motorcycle, but I would still rather balance than not, simply because you can't deny the physics and I'm keen to set my bike up to the best of my ability.