Ridged Rear End on Midbike

[Midbike Racer]

Does anyone know of any type of part that can make the rear end ridged on a midbike instead of getting a really stiff replacement shock?
Seems like if one if fabricated, it would be a great part for us.
Is this something not doable and that is why it has not been done already?

[Blitz$M.Inc.$]

id say performance and comfort is why no hardtail
even cags got rear shocks

[rednek01]

id say performance and comfort is why no hardtail
even cags got rear shocks

I thought all the true racing PB's were stiff framed front and back? dunno

[Midbike Racer]

I thought all the true racing PB's were stiff framed front and back? dunno
Thats what I thought.
I know there is a new PB out there now with a rear shock and most everything I have read is very negative about it.
Some say it is even a safety issue if it is not ridged.
I was just wondering if that would help or make a difference with the midbikes.
dunno

[rednek01]

I dont know when i get mine I will fab up a bracket that will fit where the shock fits and see if there is a difference thumbsup2

[Pinto93]

All I know is that if I had no suspension, my nuts would be crying!

[rednek01]

All I know is that if I had no suspension, my nuts would be crying!

well dont sit on them when you ride!Poke12

[swanni06]

No real racing pb have any form of suspension..thumb_down
With back suspension the rear would kick out from under you going thru a curve.
Do race go karts have any type of suspension? I am pretty sure that no track vehicle that races has much of any suspension at all...you want them low and stiff for better cornering.

[Midbike Racer]

All I know is that if I had no suspension, my nuts would be crying!
Not after the first 5 miles.
I rode my L7 50 miles on Route 66.
It hurt bad at the beginning but after about 5 miles or so, everything went numb.thumbsup2
The next day was a different story.thumb_down

[Pinto93]

Not after the first 5 miles.
I rode my L7 50 miles on Route 66.
It hurt bad at the beginning but after about 5 miles or so, everything went numb.thumbsup2
The next day was a different story.thumb_down



LOL. Fitty Miles!speechless33 Damn! Thats furthest I've ever heard of some 1 riding a PB. I really dont like when my junk goes numb, but I guess thats better than it hurting for 50miles.thinking_smilie

[rednek01]

Not after the first 5 miles.
I rode my L7 50 miles on Route 66.
It hurt bad at the beginning but after about 5 miles or so, everything went numb.thumbsup2
The next day was a different story.thumb_down

so now we can call ya numbnuts? stirthepot

[redryderaus]

A rigid rear end would not work well for several reasons:

1/ The shock absorber is there to continually adjust for changing load while cornering. Without the shock absorber the tire has to do that and it will not maintain contact with the road surface. Watch a MotoGP race when they have a camera on a bike showing the rear wheel. Watch how much it is moving, especially exiting the corner as power is applied.

2/ Without a shock absorber those load changes will be directly transmitted to the frame. They will break the frame in short order.

Hardtails are for looks, not performance.

Cheers,

red ausflag

[Midbike Racer]

A rigid rear end would not work well for several reasons:

1/ The shock absorber is there to continually adjust for changing load while cornering. Without the shock absorber the tire has to do that and it will not maintain contact with the road surface. Watch a MotoGP race when they have a camera on a bike showing the rear wheel. Watch how much it is moving, especially exiting the corner as power is applied.

2/ Without a shock absorber those load changes will be directly transmitted to the frame. They will break the frame in short order.

Hardtails are for looks, not performance.

Cheers,

red ausflag
In your opinion red, is the PB's with the rear shock a bad idea or not?
I am asking because I was thinking about getting one and most all the people said they were no good and dangerous.
dunno

[Midbike Racer]

LOL. Fitty Miles!speechless33 Damn! Thats furthest I've ever heard of some 1 riding a PB. I really dont like when my junk goes numb, but I guess thats better than it hurting for 50miles.thinking_smilie
50 miles... that was just non stop other than a fuel up.
That same weekend I put at least 200 miles on it then raced it in a CAG class the following weekend.
I really like the L7's. They are well built. Never had a problem with it.

[stuntnx7]

shocks are a good thing.......get a stiffer one like we do for these midbikes and you will be smoking a hardtail through the corners

[swanni06]

not for pocket bikes there not...go to a p/b race and see how many are runnig those crappy suspension frames..

[stuntnx7]

not for pocket bikes there not...go to a p/b race and see how many are runnig those crappy suspension frames..



they aint set up right

[swanni06]

a lucky 7 is the best a/c pocket bike made for racing ask anyone that knows what they are talking about..if it would be better with a rear shock the riders would add one IMO.I am not saying a ridgid frame would be better on bigger bikes but its the way to go on a pocket bike for racing.

[stuntnx7]

a lucky 7 is the best a/c pocket bike made for racing ask anyone that knows what they are talking about..if it would be better with a rear shock the riders would add one IMO.I am not saying a ridgid frame would be better on bigger bikes but its the way to go on a pocket bike for racing.




a bike is a bike is a bike........if you get the right shock it will be just like a GP bike keepin the tire planted instead of makin the tires work so hard bouncin and sliding around

[Supercharged]

uhhh dont you guys think if suspension was better then every bike would have it.....pocket bikes have been around for years and umm i think suspensions not something anyone looked over, if its such a great idea why does no race bikes have suspension????banghead

[mishka]

ya if we needed the suspension then every race pocketbike would have one on there bike..
its like the go karts, there is no suspension, and on track cars, there suspension is STIFF!!! and pbs have been around for years now and i sure if a suspension would be better they would have made bikes with them... IMO..

[swanni06]

uhh..a bike is not a bike..they are differences.
in full sized bikes some flex is designed in the chassis to compensate. When cornering, the sticky tires are the only things that hold you to the ground, not the suspension.
Most PB racing rules don't allow for bikes with any kind of suspension...thats another problem.
You don`t go fast enough on them to need it and if you are going over bumps big enough to make you loose that much traction..you are off the course,get back on the track.

[stuntnx7]

they make a hardtail bcuz its cheaper and easier

[stuntnx7]

uhh..a bike is not a bike..they are differences.
in full sized bikes some flex is designed in the chassis to compensate. When cornering, the sticky tires are the only things that hold you to the ground, not the suspension.
Most PB racing rules don't allow for bikes with any kind of suspension...thats another problem.
You don`t go fast enough on them to need it and if you are going over bumps big enough to make you loose that much traction..you are off the course,get back on the track.



like dude said up there....go watch a GP race and see how much the swing arm moves

[swanni06]

they make a hardtail bcuz its cheaper and easierthey make them that way cuase they handle better..go to a pocket bike forum and make a thread if a rear shocked pb will out perform a ridgid and see what they say.

[stuntnx7]

oh and when you go around corner and especially an S turn the back tire looses grip bcuz of weight transfer and if they had suspension this wouldnt happen and you would be faster

[Midbike Racer]

Here is a PB with a rear shock.
They call it the GP RS-R

[swanni06]

well I think if a 2500.00+ blata or polini pocket bike needed suspension they would add it...they make them stiff for a reason..they are not built 'cheap' either.

[Supercharged]

bluelaugh cheaper and easier.....if it was better for a pocketbike to have suspension then all bikes would have suspension, you should take swanni's advice and go get flamed at a real pocket bike forum... try it suspension for yourself and tell us how jumpin all around in the corner is?crazy_smilie

[sr20hardbody]

ok suspension on any pocket bike is stupid unless your just going to use the bike to cruise around town and go over bumps! everyone knows stiffer is better for racing look at indy cars you think they were made to handle bumps? no just high speed cornering. another thing is why dont stamas, zpf, gem, grc, polini, blata use suspension? because they're not made to just cruise around they're made for serious competition and you would lose the competition big time if you had suspension. they make these bikes like this for a reason guys not for comfort but to haul as5 think about it.

[Supercharged]

bows_smilie 20hardbody has a banshee, his opinion can be given more credit than minebows_smilie

[stuntnx7]

bluelaugh cheaper and easier.....if it was better for a pocketbike to have suspension then all bikes would have suspension, you should take swanni's advice and go get flamed at a real pocket bike forum... try it suspension for yourself and tell us how jumpin all around in the corner is?crazy_smilie




ok i guess a GP bike is just built wrong then right.........i guess suzuki needs to make there bikes hardtail....hahahah...lol....oh and i wouldnt go lookn for a pocketbike forum bcuz to me pb's suck and are clown bikes

[Supercharged]

haha yea stuntin there made wrong totally wrong...gp bikes and pocket bikes totally the same no difference...nopeidea_smilie

[stuntnx7]

whats different, hmm......you tell me one difference....they are scaled down versions....same thing

[Supercharged]

wait...is anyone agreeing with you stuntin????? b_s

go do a poll at a pocketbike site, see what they think bluelaugh

[stuntnx7]

i dont need to do a poll bcuz every1 that rides one of those dont know what there talkin bout most of the time......and they just listen to what every1 else says bcuz they dont have the knowledge it takes to comprehend

[Midbike Racer]

All I know is that when I asked on PBP, they all said it is a bad idea to race with rear suspension because it is very dangerous.
I had no idea why it was but they all seem to say not to get one so that is why I was wondering how that related to a midbike and our rear swing arm.
dunno

[stuntnx7]

All I know is that when I asked on PBP, they all said it is a bad idea to race with rear suspension because it is very dangerous.
I had no idea why it was but they all seem to say not to get one so that is why I was wondering how that related to a midbike and our rear swing arm.
dunno




if someone thinks they can go through an S turn and the wheel stay on the ground the whole time then they are the biggest idiots ive ever seen.....and every1 knows without a back tire on the ground pushin the bike it cant go anywhere

[Midbike Racer]

i dont need to do a poll bcuz every1 that rides one of those dont know what there talkin bout most of the time......and they just listen to what every1 else says bcuz they dont have the knowledge it takes to comprehend
I hear what you are saying and respect your posts but a good point was brought up...
Is polini and blata just doing it wrong?
Maybe there is something different with that small of a machine and being that low to the ground for it to be better ridged.
dunno

peace_symbol EVERYONE!!!

[stuntnx7]

yall people act like your gonna have a soft shock on there and it just bounce all over the place.....well thats just ignorant......you gotta have the right setup like every other bike in the world...

[swanni06]

[QUOTE=stuntnx7;4671]whats different, hmm......you tell me one difference....they are scaled down versions....same thing[/QUOTE
Dude I am tired of argueingrolleye0010 I know a bit more about pocket bikes then you..I have oh umm only owned about 4 how many have you?
If you think your right..which your not,get one of those turd suspension bikes and race it..that is if they will let you run..its against the rules to run a suspension bike in a real pocket bike event but you can find some teens at a grocery store lot,Go race them and you will be very embarrassed when you don`t do so well.

[stuntnx7]

I hear what you are saying and respect your posts but a good point was brought up...
Is polini and blata just doing it wrong?
Maybe there is something different with that small of a machine and being that low to the ground for it to be better ridged.
dunno

peace_symbol EVERYONE!!!




they are doin it wrong......like i said, if the tire aint planted at all times then you aint goin as fast as you CAN

[stuntnx7]

[QUOTE=stuntnx7;4671]whats different, hmm......you tell me one difference....they are scaled down versions....same thing[/QUOTE
Dude I am tired of argueingrolleye0010 I know a bit more about pocket bikes then you..I have oh umm only owned about 4 how many have you?
If you think your right..which your not,get one of those turd suspension bikes and race it..that is if they will let you run..its against the rules to run a suspension bike in a real pocket bike event but you can find some teens at a grocery store lot.
Go race them and you will be very embarrassed when you don`t do so well.




you own the crappy bikes is the reason your tryna to defend em.......and i wouldnt waste my money or own any of the CLOWN BIKES

[swanni06]

they are doin it wrong......like i said, if the tire aint planted at all times then you aint goin as fast as you CANyeah they are doing it wrong..go over to pbp and show em how to do it .thumbsup2

[swanni06]

you own the crappy bikes is the reason your tryna to defend em.......and i wouldnt waste my money or own any of the CLOWN BIKESthats true..wish I had a kickmoon1 machine like you got in your avatarbluelaugh
I am done lol

[stuntnx7]

pbp can just be deleted for all i care.....thats all kids that think they know about bikes.....

[stuntnx7]

thats true..wish I had a kickmoon1 machine like you got in your avatarbluelaugh
I am done lol





yeah i bet you do then you could throw those clown bikes in the lil trashcan by the toilet....lol

[rednek01]

Dang guys lets be mature here. Isn't this the reason we left PBP?

[swanni06]

[QUOTE=stuntnx7;4684]pbp can just be deleted for all i care...QUOTE]
Now that I can agree with you on!!

[stuntnx7]

Dang guys lets be mature here. Isn't this the reason we left PBP?





yeap sure is

[Supercharged]

uhh why dont you get yourself a suspension bike stuntin and " set it up right " and go race and win then maybe ill consider your opinion..pocket bikes have been around for years and i dont think its something anyone overlooked and i dont see any race bikes with suspension so you go and race a suspension bike as soon as possible...please i wanna see the results, keep us posted

[stuntnx7]

uhh why dont you get yourself a suspension bike stuntin and " set it up right " and go race and win then maybe ill consider your opinion..pocket bikes have been around for years and i dont think its something anyone overlooked and i dont see any race bikes with suspension so you go and race a suspension bike as soon as possible...please i wanna see the results, keep us posted




like you said, they dont let em race........sooo thats proly why you dont see any good ones bcuz no1 has set one up right......i never doubted that a hardtail is fast but im sayin.......IF THE WHEEL ACTUALLY STAYED ON THE GROUND THEN IT WOULD BE FASTER

[stuntnx7]

IF THE BACK TIRE STAYED ON THE GROUND THE BIKE WOULD BE FASTER......there i said it twice so you dont miss it...lol

[Supercharged]

i never sed they dont race them, swanni sed that..i just sed i didnt see any race pb with suspension...get ur facts straight

[stuntnx7]

i never sed they dont race them, swanni sed that..i just sed i didnt see any race pb with suspension...get ur facts straight




oh well either way..........IF THE BACK TIRE STAYED ON THE GROUND IT WOULD BE FASTER.....am i getin my point across....lol

[swanni06]

sigh..yes Stunt you did..can we get back to middies now?.......Please?

[stuntnx7]

ok i just wanted every1 to know......IF THE PB's HAD SUSPENSION THEN THE BACK WHEEL WOULD STAY ON THE GROUND AND IT WOULD BE FASTER......lol

[swanni06]

ok i just wanted every1 to know......IF THE PB's HAD SUSPENSION THEN THE BACK WHEEL WOULD STAY ON THE GROUND AND IT WOULD BE FASTER......lol

yes stunt..your OPINION cool ok middys now thats what I want to learn aboutthumbsup2

[stuntnx7]

its fact...

[Supercharged]

ok stuntin, your right pocket bikes suck because they dont have suspension....badass companys are cheap and oversee the fact that its better.....your the only one who seems to believe this so you be the only one to think its better

[Supercharged]

only 1 so you see it

[stuntnx7]

yeah ok im glad you agree....lol.......the funny thing is you think i care if someone agrees with me.....thats like sayn 2 + 2 = 4 and you say no it dont.....im just gonna think your an idiot and go on with it....lol.....good example huh

[Supercharged]

hahahah not funny but what is funny is if your right stuntin your sitting on a good mine!!!!!! go get it jack!

[stuntnx7]

was too funny......aight lets just let dude get back to his thread

[Supercharged]

ur full of it, if your so right why not be MR. KNOW EVERYTHING and start a PB revolution, your full of it....pocketbikes with suspension will never see the light of day...just remember since your " RIGHT " your sitting on millions....go race and win remember your sitting on a gold mine knowone knwos about!
idiot yourself

[Supercharged]

you have no case for arguement and you wont argue anymore cuz you stand no ground...

[stuntnx7]

ok buddy......cool.....10-4.....hahaha....lol....i got this dude writn paragraphs hes so mad

[Supercharged]

im not mad, just proving your dumb for thinking your right, i never get pissed off =)

[Blitz$M.Inc.$]

hey guys, when i was at VIR there were alot of pb's there
i was right next to team bionic and befriended a few guys
i will pm them and try to find out from the REAL racers
as for the mids, i had a hard time through a few turns cuz my shock was way to springy and making my back wheel hop like i was going over bumps
i dont think being totally ridgid would be the answer either
i think the pb's get away with no suspension simply because they are so small, the frame wont flex anough to cause damage like it WOULD on the mids
dont fight guys, were all much better friends

[rednek01]

Grow up and drop it guys come on this is rediculous thumb_down

[Supercharged]

and i dont who your talkin to, definately not anyone who agrees with your irrational hogwash ideas

[swanni06]

think the pb's get away with no suspension simply because they are so small, the frame wont flex anough to cause damage like it WOULD on the mids
dont fight guys, were all much better friends[QUOTE]


I agree with blitz on that, very good post!!....I made my point and I am done ..no use in argueing over it guys lets talk about how to make middy's better not pocket bikes.thumbsup2

[stuntnx7]

perfect example is my 4-link dragster....... it moves so the TIRES ARE PLANTED AT ALL TIMES but you cant even push down on it and make it move its so stiff but its not a hardtail which doesnt move at all and makes the tires work and you lose time

[Midbike Racer]

Dang guys lets be mature here. Isn't this the reason we left PBP?
Come on midbikers... lets not fall into the same trap.rock2

Seems PB's bring out the worst.rolleye0010

I think Blitz had a great idea.
Ask a few of the PB racers from VIR and see what they say.

Like I said, I was just wondering how this translated to midbikes. dunno

peace_symbol

[Pinto93]

Well Midbike Racer thats 2 pages of ur thread thet u will never get back LOL...Unless u were to remove it....
Like Nek said there is no more point in arguing, most of us(including myself) are over here b/c of this same crap on PBP. We all have opinions and need to express them in a mature way. So lets just drop it and see what the real pb racers say.
I understand where ur coming from Stunt but IDK if it is the same with pb's. So I'll let the experts answer.

[schofell84]

pb's do have a suspension. TIRES.

do you think they are rock solid? no, they flex to conform with bumps and the track. they just cant go fast enough to merit a real suspension. bluelaugh

[swanni06]

pb's do have a suspension. TIRES.

do you think they are rock solid? no, they flex to conform with bumps and the track. they just cant go fast enough to merit a real suspension. bluelaugh
agreed but the banshee sho hits 50mph

[sr20hardbody]

like you said, they dont let em race........sooo thats proly why you dont see any good ones bcuz no1 has set one up right......i never doubted that a hardtail is fast but im sayin.......IF THE WHEEL ACTUALLY STAYED ON THE GROUND THEN IT WOULD BE FASTER


since when have you ever seen a pocket bikes rear tire come off the ground? i know my front tire comes up from too much power but never have i heard of a rear tire coming off the ground unless you scrape the pegs and catch but other then that pocket bikes stay planted! and yes the banshee does 47mph out of the box which the acceleration is too fast so you have no choice but to gear higher which then allows you to go 57mph while still having enough power to lean far forward and pull a wheelie when the powerband hits.

[The Nutty Professor]

It seems like everyone kind of ignored Red's answer. I know I'm jumping in here late. As for the statement that Indy Cars don't have shocks or suspension (I think that's what was said) that is not correct, they do. The suspension in inboard much like the engine. All you see are the spindles but they have a suspension attached. As for shocks on Mid's and PB's we are talking oranges and grapefruits. They are both in the same family of citrus, but they ain't the same. I also read the comment about the Karts again a fine point that links all this together has been missed. A PB and a Kart are very ow to the ground and there center of gravity is very very low. The roll axis of both is low and doesn't put a lot of (?)...I'm not sure exactly what's it's called so I'll say top-heavy stress on the chassis. A Mid Bike is a lot taller which makes the CG higher and the twisting forces placed on the components of the bike are higher. The sidewalls of the tires flex more. The forks are longer so they flex. The chassis is longer and taller so it twist. A perfect example of trying to use PB style stiffness in a 1:1 bike was a early model Yamaha 500GP bike. I believe it was ridden by Wayne Gardner. The bike had a suspension of course but the chassis was so stiff the bike refused to track a line through a corner. Gardner called the bike a over engineered pig. That bike was the beginning of tuned flex as a science in the racing world. I believe a PB with a suspension would be like that Yamaha. But not having a suspension on a larger bike is...well you bring your rigid Mid to a race and I'll bring my Swheel Suspension Engineering bike and I'll let you run in front then pass and watch the video replays of you runnning off into the woods somewhere (That was not directed at a particular person. It was directed at anyone foolish enough to believe no suspension is better on anything other than a PB).

[schofell84]

gross chevrolet has nothing to do with formula one haha


BLASPHEMY !!!

[Rexcarnage]

pb's do have a suspension. TIRES.

do you think they are rock solid? no, they flex to conform with bumps and the track. they just cant go fast enough to merit a real suspension. bluelaugh

Hi - Blitz asked me to comment on this thread from a pocket bike perspective (I pitted next to Blitz at VIR).

schofell84 is partially right - the air pressure in our tires makes up part of the equation for the suspension - when the track is really bumpy I run lower pressure and vice-versa. But the pocketbike's frame is the second part of the suspension. A good pocket bike will have flex in the frame to soak up torque loads and bumps (a la suspension). Some pocket bikes are very rigid (Polini 910), and others are more flexible (BMS, GRC, etc).

The rules for pocketbike racing stipulate that the frames must be suspension-less (rigid). I can only assume that the pocketbikes still don't don't have suspensions because of complexity, weight, and space. I have been racing pocketbikes for two years and can honestly say that not having suspension has not caused me any issues. I've never had the wheels noticably leave the ground (except for wheelies). So I don't believe our pocket bikes would be faster with suspension - at VIR in the super production (39cc, 8.5hp) class I was turning 45 second laptimes - the fastest Midbike was turning 49.5 second lap times (I don't know what HP or cc his bike had).

I personally wouldn't want suspension on my pocketbike because it is already a small enough space to work in.

I have also raced by Aprilia RS50 - and I am glad that that bike has suspension - but it is almost full size. But it's suspension is on the soft side and could use a good set of adjustable shocks to tune for my weight.

Alan

[The Nutty Professor]

gross chevrolet has nothing to do with formula one haha


BLASPHEMY !!!

I know I was trying to show the suspension fact about Indy. Accept it or not Indy cars and F1 are designed the same except F1 use magic spells or something because them cars ain't natural crazy_smilie

[swanni06]

I was only talking about running a pocket bike with NO suspension..thats it

[swheels]

Well i'll say this from my experience when i test in the parking lot.Going thru one of the turns(a sweeper) theres a small rise right in the apex.With my suspension setup to firm a be leaning going through the turn and as soon as i go over the rise it wants to stand the bike right back up.:confused: I could figured it out so i tried a softer setting and went through the turn and didn't have that problem.The bike had a slight push in the front end but it stayed down in that turn.
I suspect that riding on a rigid that the frame will start to bend and break welds that you would not suspect.The metal on these bikes are made out of are very very low grade material.In fact i remember my x1 i had the stock shock on the rear.I tightened it so much that it started to break the mount.speechless33.

[kevin@holeshotz]

I read most of the first page of this thread. Personally, i love my suspension.............BUT on a pocketbike, it is not needed. What makes suspensions so great is it absorbs the force which is created. When there is no weigh to create that force there is no need to have a suspension. On a midbike, you should have a suspension, those things are heavy as balls. On a pocketbike, no. You'd be getting your ass handed to you by cags if you had a suspended pocketbike. The newer version ATM (futura i think its called now) tried to create a suspended 4 stroke pocketbike (kill two birds with one stone) and it sucked so hard it didnt make it past one race. Look at all the big and small names, GRC, BMS, GEM, Giannini, Pasini, ATM, Blata and so on NONE of them use suspensions. case closed

[stuntnx7]

see look nobody has ever tried to do it......like kevin said nobody made an effort after the first race.......if ne1 thinks a bike can be built and raced and win the first race its ever been in then they dont need to build bikes

[Blitz$M.Inc.$]

thank you very much Alan
it seems suspensions are not needed on the pb's
and even if they were, you cant have it, because its against the rules
i timed a 52-53 sec lap for myself today
the fastest mid was a watercooled 125cc

[kevin@holeshotz]

see look nobody has ever tried to do it......like kevin said nobody made an effort after the first race.......if ne1 thinks a bike can be built and raced and win the first race its ever been in then they dont need to build bikes

Years of R&D went into one bike to find out (the hard way) that a suspended pocketbike is as useful as a broken condom. I think you misread my post.....

BTW, ATM didnt produce bikes for years hyping up this suspended four stroke bike. Look where it got them?(they no longer produce pocketbikes)

[Midbike Racer]

Hi - Blitz asked me to comment on this thread from a pocket bike perspective (I pitted next to Blitz at VIR).

schofell84 is partially right - the air pressure in our tires makes up part of the equation for the suspension - when the track is really bumpy I run lower pressure and vice-versa. But the pocketbike's frame is the second part of the suspension. A good pocket bike will have flex in the frame to soak up torque loads and bumps (a la suspension). Some pocket bikes are very rigid (Polini 910), and others are more flexible (BMS, GRC, etc).

The rules for pocketbike racing stipulate that the frames must be suspension-less (rigid). I can only assume that the pocketbikes still don't don't have suspensions because of complexity, weight, and space. I have been racing pocketbikes for two years and can honestly say that not having suspension has not caused me any issues. I've never had the wheels noticably leave the ground (except for wheelies). So I don't believe our pocket bikes would be faster with suspension - at VIR in the super production (39cc, 8.5hp) class I was turning 45 second laptimes - the fastest Midbike was turning 49.5 second lap times (I don't know what HP or cc his bike had).

I personally wouldn't want suspension on my pocketbike because it is already a small enough space to work in.

I have also raced by Aprilia RS50 - and I am glad that that bike has suspension - but it is almost full size. But it's suspension is on the soft side and could use a good set of adjustable shocks to tune for my weight.

Alan
Thanks rex for the helpfull info. Welcome to the community.
I guess after reading all this...
PB's need to be ridged and midbike work well with a suspension.
I guess that is why they are ALREADY made that way.bluelaugh
Thanks for the referral Blitz!thumbsup2

[Midbike Racer]

see look nobody has ever tried to do it......
It is hard for me to believe that a ton of R&D was not put into the decision of using a ridged frame for polini and blata...
I can imagine some type of kick ass test track behind the polini factory.speechless33

[sr20hardbody]

It seems like everyone kind of ignored Red's answer. I know I'm jumping in here late. As for the statement that Indy Cars don't have shocks or suspension (I think that's what was said) that is not correct, they do. The suspension in inboard much like the engine. All you see are the spindles but they have a suspension attached. As for shocks on Mid's and PB's we are talking oranges and grapefruits. They are both in the same family of citrus, but they ain't the same. I also read the comment about the Karts again a fine point that links all this together has been missed. A PB and a Kart are very ow to the ground and there center of gravity is very very low. The roll axis of both is low and doesn't put a lot of (?)...I'm not sure exactly what's it's called so I'll say top-heavy stress on the chassis. A Mid Bike is a lot taller which makes the CG higher and the twisting forces placed on the components of the bike are higher. The sidewalls of the tires flex more. The forks are longer so they flex. The chassis is longer and taller so it twist. A perfect example of trying to use PB style stiffness in a 1:1 bike was a early model Yamaha 500GP bike. I believe it was ridden by Wayne Gardner. The bike had a suspension of course but the chassis was so stiff the bike refused to track a line through a corner. Gardner called the bike a over engineered pig. That bike was the beginning of tuned flex as a science in the racing world. I believe a PB with a suspension would be like that Yamaha. But not having a suspension on a larger bike is...well you bring your rigid Mid to a race and I'll bring my Swheel Suspension Engineering bike and I'll let you run in front then pass and watch the video replays of you runnning off into the woods somewhere (That was not directed at a particular person. It was directed at anyone foolish enough to believe no suspension is better on anything other than a PB).


i never once said indy cars have no suspension of course they do they even have computers to monitor tire pressure! i was saying they are stiff meaning stiffer for racing purposes they werent made to handle bumps but they can cut corners like a matha same with a pocket bike because of having no suspension its very stiff making it handle very well but bad with bumps. and im not dissing anyones bike if you have a gp rsr then they were made for cruising around and being comfortable with bumps but they would suck vs a half fairing cag lets say just because the half fairing cag is alot stiffer. just clearing things up here guys.

[redryderaus]

Sheesh! I log on at the end of the day to find a severe case of puberty broke out! Play nice, guys.

Rex made some very valid points about PB's. The tires, the lack of space, the weight penalty, the rules. There is also a very low CG to consider.

F1 cars actually have what little wheel movement they have built into the suspension arms. They flex and provide some travel. Because of that, the road surfaces they race on have very strict limits when it comes to bumps. Also consider their very low weight compared to the amount of rubber they have in contact with the road.

If you want to race your midbike with NO suspension at all it's fine with me. I'll stick with what I know.

Cheers,

red ausflag