under size front tires anyone?
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Addicted
2010 gts 300 super. 09 MP3 500 lite
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Thu Jun 18, 2020 9:32 am quote
I briefly considered 110 tires on my mp3 when I was buying tires. I nixed the idea as i am pretty fussy about what i like in tires. I had just recently bought conti twists for my gts 300 and loved them. so I knew I would be happy with the 120 twists up front. I have 6500 miles on them, three rear tires later. The fronts are great. no complaints at all. they look they will last another 10k.

so twists not offered in the 110 size. I found a tire I know I like in that size. so I think I am going to give it a try. so why would I do this?

less rotational mass. more responsive acceleration.
faster more responsive steering.
more responsive brakes.

these are the things I notice when making the undersize switch on two wheelers. and there are two this time. will report back.



Last edited by jerryd on Fri Jul 03, 2020 8:57 am; edited 1 time in total
Ossessionato
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Thu Jul 02, 2020 6:23 am quote
Just bear in mind that going down in tyre size will reduce tyre contact patch size so 'more responsive' braking is unlikely, it's probably worse in an emergency. You may be noticing the slight reduction in carcass weight though and that may be fooling you.

In addition, the tyre loading capacity is nearly always reduced. I'd check that. Further, reduced tyre size can result in more punctures especially on the rear wheel.
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Thu Jul 02, 2020 8:52 am quote
brake response I refer to is how many fingers needed to stop. less fingers will be needed.

brake response you refer to would be better termed braking power. ie shorter brake distance.

I have never found skid point on the 120s. I think bike would flip over first. I dont need more braking power. it is nothing short of amazing. I am sure contact patch varies with tire brands. but far more important factor is coefficient of friction of the rubber. a smaller contact patch can out brake a tire with bigger contact patch if friction is higher.

I have three scooters running undersize tires and they are all intelligent choices that increase the overall performance of the bikes. sounds to me more like you are jealous you cant try alternate tire sizes in your country. too bad for you. I would hate living there.

but thanks just the same for your input.

lots of people in usa use oversize tires. they are after lower rpm cruising, better gas mileage, and longer service interval. none of which is important to me.
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Gilera Fuoco 500ie
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Thu Jul 02, 2020 10:53 am quote
110 can but remind its a motorcycle not a moped 50cc most 110 12inch have a J speed indication 70km/h

110/90/12 P or higher will work

everting less then speed indication P will blow out P are rated at 150km/h
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2008 MP3 500, 2013 BV350, 2020 Vespa Sei Giorni
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Thu Jul 02, 2020 1:23 pm quote
As stated my concern would be the speed rating, can you find an "S" rated 110/70 x 12?
Ossessionato
Gilera Fuoco 500ie
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Thu Jul 02, 2020 11:44 pm quote
you dont want 110/70/12 to hard on the bearings
Addicted
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Fri Jul 03, 2020 7:01 am quote
the tire will be contiscoot. my new favorite tire.
Ossessionato
Gilera Fuoco 500ie
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Fri Jul 03, 2020 8:01 am quote
with which speed rating?
Addicted
2010 gts 300 super. 09 MP3 500 lite
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Fri Jul 03, 2020 8:49 am quote
p rated. 47 load. so I am good to 350kg weight on front tires to 150kph

and my gut feeling is this change will be ridiculously good. it will go down as one the best mods done as of yet.
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Gilera Fuoco 500ie
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Fri Jul 03, 2020 8:57 am quote
conti only have 110/70's to low 6.5cm high will be a bearing killer not only the stearingbearings also wheel bearings

Also speedsensor will be off by 20% so front tyres will be doing 90 mph when going 75 so P rated wont work then
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2010 gts 300 super. 09 MP3 500 lite
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Fri Jul 03, 2020 9:01 am quote
ok. I look forward to killin some bearings then.
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2008 MP3 500, 2013 BV350, 2020 Vespa Sei Giorni
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Fri Jul 03, 2020 12:48 pm quote
Just remember Maksor knows as much or more than Piaggio about what can be done to an MP3.
He is in the process of making an MP3 850.
Addicted
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Fri Jul 03, 2020 2:37 pm quote
as long as you keep in mind I am allowed to modify my scooter how I see fit. and there may be readers now or in the future that want to hear about those results.

also keep in mind I dont go in his threads and warn him the scooter frame, tires, front end bearings was not designed for an 850 engine and it will brake when he does it.
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Gilera Fuoco 500ie
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Fri Jul 03, 2020 10:27 pm quote
you don't know how i am going to build it

as a company i rebuild 6 GP800 now to a 986cc doing 235km/h
we change the brakecalipers for the one of a cbr600rr front and rear different tyres to match the speed also doing other things to be save

the fuoco 850 going to get most of is weight on the rear wheel i don't wanna change the bearing every 5000km on it

front rims will be at least 13" or custom made 14" with matching tyres

what you are doing is opposit getting more weight on the front due to a lower tyre and turning them 20% faster

i know how well maintained the roads are in the US good luck
Addicted
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Sat Jul 04, 2020 12:59 am quote
sounds like maksor will continue to ad weight to his mp3 to make it less fun, and I will continue to remove weight from mine to make it more fun.
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Gilera Fuoco 500ie
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Sat Jul 04, 2020 3:50 am quote
No i keeping it safe what your doing is playing with your own and other peoples lives


when your tyre blows and you crashed with a car behind you don't wanna know the out come
Addicted
2010 gts 300 super. 09 MP3 500 lite
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Sat Jul 04, 2020 5:19 am quote
contrary to what your evil self wishes would happen so you can bring attention to yourself my bike will maneuver better which will make bike safer for me and everyone around me.

will tire be spinning 20% faster like maksor says? no its 3%
will my bearings wear out faster like maksor says? no there is less rotational mass, so less load on bearings.
will the 47P rated tires blow because I exceed ratings? no. front end of bike weighs 310lbs with me on it. load capacity on front is 770lbs and at 100mph. I have never been over 80mph on a scooter. so no tires will be blowing because maksor say so.

its amazing to me you have an apparent inclination to bother people for no good reason.
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Gilera Fuoco 500ie
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Sat Jul 04, 2020 5:44 am quote
If you want to get personal be my guest i am only trying to advise so other don't stupid things why is Piaggio Using S rated now then

110mm 70% is 7.7cm/77mm 120 /70% is 8.6cm /86mm 77mm times 112% is 86.2mm

speedo is of by at least 10 to 15% on the 12" so they are turning 10% faster
adding 10% for the lower 110 is still aprox. 20%

and if weight is an issue go vor J rated with 10" vespa rims they are less weight then the P rated
Addicted
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Sat Jul 04, 2020 5:55 am quote
you want respect you wont get it from me. you come in all my threads and say dumb stuff.

first you post tire will be spinning 20% faster.

now you ad math and its now a miscalculated claimed 10%

its 3%. at least do some proper calculations. maybe start with a tire size calculator.

https://tiresize.com/comparison/
Ossessionato
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Sat Jul 04, 2020 11:47 pm quote
jerryd wrote:
you want respect you wont get it from me. you come in all my threads and say dumb stuff.

first you post tire will be spinning 20% faster.

now you ad math and its now a miscalculated claimed 10%

its 3%. at least do some proper calculations. maybe start with a tire size calculator.

https://tiresize.com/comparison/
Jerry, no one is having a go at you. Why do you always go down the route of making personal attacks when someone is just trying to add to stuff you are saying and be helpful. If you are an engineer as you say you are then you should be welcoming comments and discussion. If you don't want people to comment then don't post about it. Some people on here are just trying to be sure you are going to be safe doing what you are doing. And it's important that newbies and others who may try to do what you are doing are aware of the risks. Maksor is brilliant at what he does. That's very apparent, and I can tell you his comments are justified. Be very careful with the tyre ratings, I'm not sure you understand fully why they are there, based upon your comments. Reducing tyre sections is rarely a good idea from the contact patch size point of view and lots of other factors. You are unlikely to make your bike safer or better in any way over what the manufacturers have done by doing that. Likely it will be less safe. Sometimes you do say some strange things with no actual grounding in reality which makes some of us wonder about your competence. No disrespect intended, you have some good knowledge on many things, we know that. But sometimes care is needed. Good luck with whatever you do and keep posting. You're our test guy, just be careful!
Addicted
2010 gts 300 super. 09 MP3 500 lite
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Sun Jul 05, 2020 12:59 am quote
when someone says a tire will be spinning 20% faster when the real data is 2.9% faster that is not brilliant in any way shape or form. its not helpful. its being argumentative. and there may be readers who miss out on a good mod because we allow such stupidity to go unchecked. worse that that there may be readers who believe the 20% faster as a truth. which if true would make me the idiot.

when I put a beo rear rim on my mp3 . maksor comment was "wont work, offset is wrong"
forgive me but where is this brilliance you speak of? that is not being helpful. his statement was not correct, not helpful, and when there is a reader who thinks I put a rim on my bike with the wrong offset it makes me look stupid.

that is just two examples. I can give you many more when I go look at my posts. then I got to post to defend more stupidity with you coming in here and saying "I am not sure you understand tire ratings" are you for real? thats being supportive of maksor stupid 20% faster statement.

then there is the bearing statements. also 100% opposite of what is true. his statements are not 100% justified like you say. in my book they are 100% disruptive when you post shit that aint true just so you can look smarter than everyone else.

my yamaha majesty is using undersize tires front and rear. 120/80-14 to 120/70 in front and 150/70-13 to 140/60-13 in the rear. the bike is NOT dangerous in any way. quite the contrary. it is SAFER in every way shape and form. and MUCH more enjoyable to ride. the end result here will be people like you and maksor and sadly any reader will miss out on such joy. the true data gets lost in the constant unnecessary banter.
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2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Sun Jul 05, 2020 1:08 am quote
Hello jerry,

Ok it's whatever you think. But just be aware that putting smaller contact patch tyres on any bike, especially a heavy bike like the MP3, is not a good idea. Potential issues are: increased puncture risk, increased risk of blow outs, reduced grip in the dry and the wet etc etc, plus a load of stuff that I'm not mentioning. Your perceived benefits don't actually exist in real life. But it's up to you, as you say.
Addicted
2010 gts 300 super. 09 MP3 500 lite
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Sun Jul 05, 2020 1:16 am quote
"Your perceived benefits don't actually exist in real life"


oh. really?

less rotational mass. more responsive acceleration.
faster more responsive steering.
more responsive brakes.

the above characteristics make the bike safer. steering clear of danger is a most important safety factor. making a bike more maneuverable may not be important to you but it is to me.

Last edited by jerryd on Sun Jul 05, 2020 5:17 am; edited 3 times in total
Ossessionato
Gilera Fuoco 500ie
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Sun Jul 05, 2020 1:38 am quote
Fronts wont make accelaration quicker, there is no drive on them or you most have a very special bike
Smaller tires wont brake better/ faster they skidd faster less contact
Steering is only better some weather condations most of it will be crap Rain and when its to hot for in stand then the rubber will be a lot softer

And if you can't stand people say it isn't a good idea then there is no place on a forum and everything else what ever do what you want glad i life on the otherside of the world

and this is the last time i reacted
Addicted
2010 gts 300 super. 09 MP3 500 lite
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Sun Jul 05, 2020 1:55 am quote
"Fronts wont make accelaration quicker, there is no drive on them or you most have a very special bike "

this is a stupid statement and has no place on any forum. reducing rotational mass will indeed allow the bike to accelerate faster. EVEN ON FRONTS.

more BAD data from a know it all.
Ossessionato
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Sun Jul 05, 2020 5:34 am quote
Jerry, the perceived advantages of less rotational mass is so small as to be almost invalid. The weight difference between the two tyre sizes you propose is very little and will barely make any difference whatsoever. It cannot improve braking at anytime no matter what you believe. There will be a tiny tiny difference is gyroscopic weighting of the steering as you ride but again it's so small that it's not worth worrying about and won't be noticeable to most people.

The main concerns which are a negative, and very real are the increased risk from skidding under braking and while cornering due to the decreased tyre contact patch. There is no denying that reduced contact patch, no matter what the rubber, is a bad thing certainly on a road going motorcycle or scooter. And of course for lots of reasons this increases the risk of punctures and blow outs. Tyre sizes are very carefully researched and tested by manufacturers to be a combination of what's best for your safety (this is the number 1 thing), acceptable wear rates and longevity. So again, reducing tyre sizes increase tyre wear, likely hood of punctures and blowouts, increases the risk of skidding and sliding, and can cause some other issues I won't go into here.

And just so you know, not trying to diss you in anyway. I kinda admire your experiments and tenacity in having a go at these things but one has to be careful about how you go about some of these things and in what you tell folks on an open forum. It could lead to someone else doing the same thing and actually believing some of your claims, and maybe even having an accident. Cheers jerry!
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2010 gts 300 super. 09 MP3 500 lite
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Sun Jul 05, 2020 7:57 am quote
I dont agree with the things you are trying to sell me. I am actually making changes and observing the results. my modifications to my bikes are doing what I say they are. I am not misleading people to try things they shouldnt. I am sharing modifications and the results. both good and bad.

my honda helix cn250 will be my good example here.

stock tire sizes 110/100-12 120/90-10

the bike came with a 120/70 front when I bought it. it was a horrible cheap tire so I dont have much comment on it. but that tire was 2.1 inches smaller in diameter. than stock. I first install stock sizes pirelli sl26. turns out those tires suck. both tires were out of round and vibrated the bike. I didnt like what happen to the steering response with the tire size change in the front. but didnt want a 1 inch drop in ground clearance by using 120/70. so I look for a compromise. I choose the 110/90-12. this tire is about .9 inch shorter than stock. I use shinko s007. absolutely lovely change. bike drive fabulous with that size tire. no way in heck I would ever go back to the stock size.

then we apply everything you say. a. not what size came on bike. dangerous. increased flat potential. etc. all BULL DROPPINGS. the 110/90 is the stock size front on a honda big ruckus ps250 . from factory p250 is 30lbs heavier than a cn250 and same engine weight and power. all your theories go right out the window.

when the the crappy sl26 rear finally wore out I wanted a matching shinko for rear. the s007 only come in 130/90-10. I installed that tire. drove bike one hour and came home and ordered 120/90 for it. the 130 killed the lovely personality the bike had. there was no getting used to it. not funny thing is I found people running the 130 and loving it. and that is why I gave it a go,
Ossessionato
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Sun Jul 05, 2020 4:39 pm quote
So to get this right, you put undersize tyres on your bike because the proper size tyres were out of round (faulty) and you didn't like the way the bike handled with those tyres fitted! Hmmm that's very interesting. Not quite sure you understand tyres as well as you think you do jerry. You certainly don't understand the science. But hey ho, carry on captain. Hope it all works out ok for you.
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2010 gts 300 super. 09 MP3 500 lite
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Mon Jul 06, 2020 1:15 am quote
ironic. very clear you dont understand them at all. you constantly try to instult my intelligence in all your posts. your posts are indeed useless. whatever makes you happy dude. you are horrible excuse for a man.

bottom line I have loads of experience switching tire sizes with experiences to share.

you live with politics and have no experience switching tire sizes. but you know all about it.

so no, you didnt get it right. you clearly didnt read what I wrote and you learned nothing from it. only where your next insult would be.
Hooked
Piaggio MP3 500
Joined: 21 Nov 2017
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Location: Austin, TX
Mon Jul 06, 2020 6:58 am quote
I'm not of the opinion that a slightly smaller tire will have that much less of a contact patch. Think of a balloon pressed against a flat surface- the contact patch of a 3' balloon will be the same as the contact patch of a 3" balloon if they have the same air pressure and are pressed down by the same weight. Now, there's a small difference based on the sidewall flexibility, but it's really the air pressure in the tire that makes the difference in the regime where balloon tires are designed to work- where sidewall flex is minimal for easy rolling but the pressure is low enough where the air pressure allows some flex. So if you're concerned about a maybe 3% difference in contact patch area, then drop the air pressure in the smaller tire by a PSI. That will increase the contact patch by 3%.

More concerning would be the speed rating and load ratings of the tires. The last thing you want is the tire overheating and delaminating. But really, the MP3 shares the load on two front tires, so we're not talking about a lot of stress on the tires. I for one wouldn't worry a bit about two new tires that were one size smaller than stock, as long as they had the same speed and load rating.
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2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Mon Jul 06, 2020 8:18 am quote
jerryd wrote:
ironic. very clear you dont understand them at all. you constantly try to instult my intelligence in all your posts. your posts are indeed useless. whatever makes you happy dude. you are horrible excuse for a man.

bottom line I have loads of experience switching tire sizes with experiences to share.

you live with politics and have no experience switching tire sizes. but you know all about it.

so no, you didnt get it right. you clearly didnt read what I wrote and you learned nothing from it. only where your next insult would be.
I see you have reverted to type jerry. It was not my intention to pee you off. Just to point out some of your claims are not 'quite right' in-spite of what you 'may feel' about them. I do have many years of experience jerry in not just engine design and development, but also developing frames, suspension, brakes, and yes tyres figured in there too. So from 'one horrible excuse for a man', for goodness sake be careful with what you are doing. Sorry you have become so peeved at someone questioning your claims. It's just you come out with some really weird stuff sometimes, and yeah, it's not very weird this time, just a bit weird.
Veni, Vidi, Posti
MP3 500, GTS 250 (both 2008 MY), 2012 Honda NC700 DCT
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Posts: 6148
Location: Madison, Wisconsin
Mon Jul 06, 2020 10:15 am quote
Stromrider wrote:
jerryd wrote:
ironic. very clear you dont understand them at all. you constantly try to instult my intelligence in all your posts. your posts are indeed useless. whatever makes you happy dude. you are horrible excuse for a man.

bottom line I have loads of experience switching tire sizes with experiences to share.

you live with politics and have no experience switching tire sizes. but you know all about it.

so no, you didnt get it right. you clearly didnt read what I wrote and you learned nothing from it. only where your next insult would be.
I see you have reverted to type jerry. It was not my intention to pee you off. Just to point out some of your claims are not 'quite right' in-spite of what you 'may feel' about them. I do have many years of experience jerry in not just engine design and development, but also developing frames, suspension, brakes, and yes tyres figured in there too. So from 'one horrible excuse for a man', for goodness sake be careful with what you are doing. Sorry you have become so peeved at someone questioning your claims. It's just you come out with some really weird stuff sometimes, and yeah, it's not very weird this time, just a bit weird.
Got to hand it to you Stromrider, you have the patience of Job.
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Neutrino MP3 492.7 AK, 2013 Moto Guzzi Norge
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Mon Jul 06, 2020 12:15 pm quote
Madison Sully wrote:
Stromrider wrote:
jerryd wrote:
ironic. very clear you dont understand them at all. you constantly try to instult my intelligence in all your posts. your posts are indeed useless. whatever makes you happy dude. you are horrible excuse for a man.

bottom line I have loads of experience switching tire sizes with experiences to share.

you live with politics and have no experience switching tire sizes. but you know all about it.

so no, you didnt get it right. you clearly didnt read what I wrote and you learned nothing from it. only where your next insult would be.
I see you have reverted to type jerry. It was not my intention to pee you off. Just to point out some of your claims are not 'quite right' in-spite of what you 'may feel' about them. I do have many years of experience jerry in not just engine design and development, but also developing frames, suspension, brakes, and yes tyres figured in there too. So from 'one horrible excuse for a man', for goodness sake be careful with what you are doing. Sorry you have become so peeved at someone questioning your claims. It's just you come out with some really weird stuff sometimes, and yeah, it's not very weird this time, just a bit weird.
Got to hand it to you Stromrider, you have the patience of Job.
I have to 2nd this opinion as well.

I have stayed out of this thread because I don't want to pile on. But since I am posting I will say Maksor and Stromrider have ALOT of extensive knowledge that I personally respect highly.
Hooked
2008 fuoco
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Wed Jul 15, 2020 1:39 am quote
Certainly my fuoco handles better with the 110/70 13 citygrips over the 120/70 12 citygrips ,wheather thats because of the marinally narrower tyre ,the very slightly taller tyre, weight difference ( if any) or a slight change in headstock angle who knows but it does make a difference. By putting slimmer tyres on it has not made it more unsafe .
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2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Wed Jul 15, 2020 5:24 am quote
3legsofman wrote:
Certainly my fuoco handles better with the 110/70 13 citygrips over the 120/70 12 citygrips ,wheather thats because of the marinally narrower tyre ,the very slightly taller tyre, weight difference ( if any) or a slight change in headstock angle who knows but it does make a difference. By putting slimmer tyres on it has not made it more unsafe .
13" wheels slightly make up for the reduced contact patch that you get on a 12" wheel contact patch size. In other words the contact patch will only be reduced by a very small amount when running 13's, so it's not too bad, making only the slightest loss to frictional adhesion.
Hooked
Piaggio MP3 500
Joined: 21 Nov 2017
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Location: Austin, TX
Wed Jul 15, 2020 5:53 am quote
Maybe I didn't get my point across-

In the tires we're dealing with, the size of the contact patch is more dependent on tire pressure than the diameter of the wheel and the width of the tire!

The handling difference between 13" thin tires and 12" fat tires, for the same pressure, is due almost entirely to the *shape* of the contact patch, any gyroscopic differences, and any differences due to the geometry of the steering. *Not* the area of the contact patch.
Hooked
2008 fuoco
Joined: 19 Jul 2015
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Location: United Kingdom.
Wed Jul 15, 2020 11:53 am quote
3legsofman wrote:
By putting slimmer tyres on it it has not made it more unsafe .
If it has i blame piaggio
Ossessionato
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Thu Jul 16, 2020 12:53 am quote
Squeazel wrote:
I'm not of the opinion that a slightly smaller tire will have that much less of a contact patch. Think of a balloon pressed against a flat surface- the contact patch of a 3' balloon will be the same as the contact patch of a 3" balloon if they have the same air pressure and are pressed down by the same weight. Now, there's a small difference based on the sidewall flexibility, but it's really the air pressure in the tire that makes the difference in the regime where balloon tires are designed to work- where sidewall flex is minimal for easy rolling but the pressure is low enough where the air pressure allows some flex. So if you're concerned about a maybe 3% difference in contact patch area, then drop the air pressure in the smaller tire by a PSI. That will increase the contact patch by 3%.

More concerning would be the speed rating and load ratings of the tires. The last thing you want is the tire overheating and delaminating. But really, the MP3 shares the load on two front tires, so we're not talking about a lot of stress on the tires. I for one wouldn't worry a bit about two new tires that were one size smaller than stock, as long as they had the same speed and load rating.
Yes, you got your point across very nicely Squeazel. I can see you are a man of science like myself.

The only issue is our tyres are not balloons and your balloons do not have a dynamic situation to deal with like our bike tyres. Both of your balloon sizes under dynamic situations, with the same pressures in them, will alter their contact patches with differing degrees of load and a mismatch between the two will occur. The contact patches will differ. The smaller balloon will be less effective with it's contact patch.

The loading on tyres is variable as we ride, from lots of different directions and the contact patch is dynamically changing all the time as is pressure and temperature. Contact patch will vary by as much as 25% or more on an average scooter tyre as we ride (as per our testing). This is also dependant on tyre profile, tyre size, pressure, loading and speed rating and of course as said, temperature. So simply put, contact patch become smaller and larger and is a variable. As we ride the tyre pressure is also changing all the time as it heats up and cools down during a ride. We measured tyre temperatures on a rolling road, and on a real ride on a front tyre fitted to a 500 Honda and the fluctuation was incredible on a 25 mile ride. Tyre pressure increased by as much as 5.5psi and then dropped it again as we rode into town. This all dynamically affects the tyre contact patch. A 'thinner' tyre with reduced contact patch over a wider tyre normally requires a higher tyre pressure to sustain the proper loading which further reduces the contact patch across the board under all dynamic situations. Add in the other forces and a 'thinner' tyre becomes less effective.

Now as I said to Jerry on what he has done there is not a huge difference, and that of course is what you are saying. However there are circumstances where that difference can make a substantial alteration to safety. We didn't spec tyres sizes and pressures lightly on bikes we had a hand in designing. In other words, stick with the right tyre sizes as specced. They do work best in all circumstances, we did the hard work to make sure they do.
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Sat Aug 22, 2020 3:57 pm quote
Jerry, you come up with some very interesting ideas, and what I like most about them is that you actually find out of they work or not. Keep at it and never let the Colin Robinsons of the world sap your motivation or try to convince you a curve ball is an optical illusion. It never occurred to me until you mentioned it here, but I am going to try what you did with your Majesty on Marcia's scooter.

A lot of people like the new Heidenau K80 motard tires. People are using them on gokarts, and supermoto races. You can get that one in a 110/70-12 with a decent speed rating. you can get the Conti Twist in a 110/90-12 with a decent speed rating as well. the K66 is a very popular flat track tire, so if you want to have fun in the dirt, that might be a consideration.
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2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
Joined: 11 Jun 2011
Posts: 3006
Location: East Anglia, a dryer region of the UK than Israel
Mon Aug 24, 2020 2:17 am quote
Question for you Motovista. Sine you have mentioned 'Colin Robinson' many times in various threads, who is he?
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