what have you done to your "bike" today

[8541Hawk]

WHEELSLIP (%)

Funny anytime I have brought up wheel slip A.K.A. tire slip I've been told I'm mad as a hatter or a flat earther....

[KermitLeFrog]

WHEELSLIP (%)

Funny anytime I have brought up wheel slip A.K.A. tire slip I've been told I'm mad as a hatter or a flat earther....

Our tyres are slipping (as opposed to sliding) nearly all of the time we are riding. It's an interesting phenomenon that most people (I exclude yourself) do not understand. OK, here goes:

Solid materials can only transmit a force by deforming. For your rubber to transmit any force (accelleration, braking, cornering) to the ground it needs to bend. The easiest way to understand this is to follow a block of a tyre as it rotates around the wheel. Out of contact with the ground it is undeformed. When it hits the ground it sticks to the ground. It is NOT sliding against the ground (except in exceptional cases). The torque from the wheel bends the rubber which transmits the force to the ground. The wheel moves further than the contact patch. When the same block leaves the ground it springs back to its undeformed shape ready to do the same thing the next time it contacts the ground. The perifery of the wheel is moving at a different speed to the ground. This is tyre slip.

All power transmitting wheels do this. Even solid steel train wheels although in that case the slip is very, very small.

[8541Hawk]

Well the comment of "it is not sliding against the ground" is where things go wrong because it is spinning faster than the bike is going. For a mental picture of this in the extreme is a bike leaving a big darkie coming out of a corner. The bike is accelerating ever though the rear is spinning trying to create enough friction to generate traction. Which is tire slip. The key to remember is to create traction you first need friction or two surfaces moving at different speeds.
This happens to a much lesser extent ever time you accelerate or even just maintaining speed. The reason why the Ape lists "wheelslip" is that it is critical on a bike with ABS and\or traction control. If the system did not account for tire slip it would apply the brakes every time you tried to accelerate due to the rear wheel spinning faster than the front.
I have posted links to published articles on the subject and have given examples though still told I am a loon but I'll try one last time. If the tire is not slipping when driving the bike forward can you explain why the center of the rear tire wears much quicker than the front? they both travel the same distance at the same speed (if there is no tire slip). Also why does the wear on the rear accelerate the faster you ride the bike but really does not change the wear rate of the front tire? Finally why does the speedo get farther from true speed the faster you go when driven by the gearbox but one that reads from the front wheel stays true?
My answer is tire slip.
The rear tire needs traction to drive the bike forward. In order to create traction it first needs to create friction, the only way this can happen is if the tire is slipping slightly.
I guess one of the guys with the newer Apes could add some info. I would like to see the "wheelslip" data as it should show that the % of wheelslip increases with speed. This happens because the rear needs to create more traction to overcome wind resistance. The only way to get more traction is to create more friction or slip a bit harder. So believe it or not it does happens.....Then again I've always been crazy but its kept me from going insane.

[MacV2]

Nue Reds first run out of the year...Weekend at Joneseys...

Ran fine after Fridays exhaust blow issues...But noticed on way home no Indis...or Horn & when got home no brake lights either... Prob just a fuse but it can wait till tomorrow...

Chicken stripps you say ???

[sirch345]

Good to see Nue Red out and about again Mac

Chris.

[freeridenick]

Finished off repairs to the loom and rewrapped it. Also found a speed sensor I'd stupidly stripped part of a wire from so repaired that too. Full road loom ready to go on the bike and space on the bench ready too start the engine rebuild. Cases back from coating tomorrow.

Sent from my Pixel 5 using Tapatalk

[MacV2]

Just a minor tinker in the cave...

Cleaned some bit's up & refreshed a set of callipers...

Back into can't be arsed mode now.

I did lower the weeds front & back before the tinker sesion so wasn't a compleatly wasted day...

[ItsaKeeper]

Not quite today but I have been dipping in and out over the last few days to get my 03 firestorm back on the road again after my RH low side.

I finally cleaned the bike which has been under wraps since the Scottish monsoon last August!

Removed my scraped rear tailpipe and replaced with an NOS tailpipe only to find out that the NOS pipe was from a pre-2002 model and narrower in the midsection...bummer. It fitted okay but looked skinny odd so removed and spend a while removing as much of the scrapes on the old pipe with various garryflex sanding blocks, upshot is that it's good enough to go back on.

The exhaust was leaking at the front header so luckily I managed to remove the both nuts, although a stud also came out but all intact. Had applied plusgas twice a day for 3 days and soaked a couple of pieces of sponge and stuck them on the nuts in an attempt to constantly feed them plusgas. Took my time and very slowly tightened and loosened until they freed up, happy with that. Cleaned up the area around the header and the clamp, removed the copper washer in readiness to replace with a new washer.

Removed fairing and fitted a new right hand outer part of the fairing and an inner left hand part that has been cracked since I got the bike in 2013, fairing looks great and an added bonus was that the old outer fairing had a small scratch that bugged me although not as much as the road rash on the rest of it

My to do list is now to replace the remaining scraped / broken parts, mirror, indicator, brake lever, handlebar bar end and inner weight that snapped, easy stuff. I also need to replace the RH crankcase cover, so will by default do an oil change, coolant flush n change. I have all the new parts and my intent is get the bike back to absolute standard.

I have been searching this forum it seems every five minutes to double check I'm doing the right thing and to learn from the experience here. I also print the pages from the manual that relate to the work I'm doing to triple check.

[fabiostar]

a few days ago now. rolled the big sofauki up to mot, no problems not even a mention of the pipes and they aint quiet

[sirch345]

Just a minor tinker in the cave...

Cleaned some bit's up & refreshed a set of callipers...

Back into can't be arsed mode now.

I did lower the weeds front & back before the tinker sesion so wasn't a compleatly wasted day...

That should make good for the photo shoot

The exhaust was leaking at the front header so luckily I managed to remove the both nuts, although a stud also came out but all intact. Had applied plusgas twice a day for 3 days and soaked a couple of pieces of sponge and stuck them on the nuts in an attempt to constantly feed them plusgas. Took my time and very slowly tightened and loosened until they freed up, happy with that. Cleaned up the area around the header and the clamp, removed the copper washer in readiness to replace with a new washer.

I'm also a fan of Plusgas, I like the way you used pieces of sponges there

Chris.

[AMCQ46]

Not quite today but I have been dipping in and out over the last few days to get my 03 firestorm back on the road again after my RH low side.

I finally cleaned the bike which has been under wraps since the Scottish monsoon last August!

Removed my scraped rear tailpipe and replaced with an NOS tailpipe only to find out that the NOS pipe was from a pre-2002 model and narrower in the midsection...bummer. It fitted okay but looked skinny odd so removed and spend a while removing as much of the scrapes on the old pipe with various garryflex sanding blocks, upshot is that it's good enough to go back on.

The exhaust was leaking at the front header so luckily I managed to remove the both nuts, although a stud also came out but all intact. Had applied plusgas twice a day for 3 days and soaked a couple of pieces of sponge and stuck them on the nuts in an attempt to constantly feed them plusgas. Took my time and very slowly tightened and loosened until they freed up, happy with that. Cleaned up the area around the header and the clamp, removed the copper washer in readiness to replace with a new washer.

Removed fairing and fitted a new right hand outer part of the fairing and an inner left hand part that has been cracked since I got the bike in 2013, fairing looks great and an added bonus was that the old outer fairing had a small scratch that bugged me although not as much as the road rash on the rest of it

My to do list is now to replace the remaining scraped / broken parts, mirror, indicator, brake lever, handlebar bar end and inner weight that snapped, easy stuff. I also need to replace the RH crankcase cover, so will by default do an oil change, coolant flush n change. I have all the new parts and my intent is get the bike back to absolute standard.

I have been searching this forum it seems every five minutes to double check I'm doing the right thing and to learn from the experience here. I also print the pages from the manual that relate to the work I'm doing to triple check.

Glad the see that you are back on here and rebuilding the bike to its best.

How's the shoulder after the low Side?

[ItsaKeeper]

Thanks for asking Al

My shoulder has recovered fine and my clavicle is loving its new position. I have ruined my beach shoulder symmetry but have been quietly working on growing a beer belly as a distraction point if I ever take my shirt off at the beach

[MacV2]

Got this 97 Storm at mine from a guy off FB who lives in Gillingham.

Thing is a bit of a munter & strangely for a 97 it has pairs fitted...

Any how it's running but has major carb fart issues & when it gets up to 1/4 hot just cuts out...

So had a tinker with it the other day made sure all the pipes were OK... The pipe from the Pairs can to the air box was off so replaced that for a start. Seemed to run a bit better bit still doing it...

Started it up again yesterday when Jonesy was here, he said it sounds like the carbs are in need of a balance...

The owner told me he had balanced them but there is no take off on the front & the rear has no T peice...

Anyhow today I have had the carbs off fitted a front take off, used a T pice vac pipe off another bike. Set the air screws to factory...Boxed it back up, carbs are in balance but it still runs like a pig...Carb farting & cutting out...

As I have to strip it all back down to take the take off's back off, I'll try a differnt set of carbs on it tommorrow & try a differnt set of coils...

Cant be arsed to do it today...

Bloody ball ache but he's comming over on wed's morn, might be having a deal with a swap & cash for Hamburg...

[KermitLeFrog]

Well the comment of "it is not sliding against the ground" is where things go wrong because it is spinning faster than the bike is going. snip...

I should have made myself a little more clear. First off the %slip data for the Ape is simply the difference between the front and rear wheel. It doesn't differentiate between what I called slip and what I called slide. Rubber can maintain friction with the ground without it actually sliding. Van de Walls forces and all that. The rubber makes a chemical bond to the ground. This chemical bond is made and broken very fast but each time it happens and little bit of the rubber is removed. If you run a rubber tyre against a roller, with no power transfer between the two, the rubber will still wear away.

You are correct. Only by having "slip" can a tyre transfer a force to the ground but this is not always due to the tyre sliding over the ground.

The "slip ratio" is a measurement much favoured but makers of ABS and traction control. It's nothing to do with "slip angle", a different beast entirely. As the slip ratio between a driven (or retarded) wheel and the control inceases the coefficient of friction increases linearly before falling off a cliff. How to activate ABS/traction control at which point on this graph and keep it there is the Holy Grail and quite a few PhDs have been granted on this subject. It's complicated.

As far as I know no one has dissassembled the coding for the ABS/traction control on the Ape. The engine control has been partially decoded but not the ABS/traction which takes inputs from an Inerial Measurement Unit (IMU) which give acceleration data in (I believe) six axes as well as other stuff like the slip ratio. It's great fun playing around with it

[8541Hawk]

I guess all this could be much easier with a simple google of the term "tire slip" as the fist link has this:

https://en.wikipedia.org/wiki/Slip_(vehicle_dynamics)

In (automotive) vehicle dynamics, slip is the relative motion between a tire and the road surface it is moving on. This slip can be generated either by the tire's rotational speed being greater or less than the free-rolling speed (usually described as percent slip), or by the tire's plane of rotation being at an angle to its direction of motion (referred to as slip angle).

In rail vehicle dynamics, this overall slip of the wheel relative to the rail is called creepage. It is distinguished from the local sliding velocity of surface particles of wheel and rail, which is called micro-slip.


Yes I am referring to Longitudinal slip which is generally given as a percentage of the difference between the surface speed of the wheel compared to the speed between axle and road surface

I haven't even come close to touching on Lateral slip which has more to do with cornering and is a different beast.