ninjette.org

Go Back   ninjette.org > 2008 - 2012 Ninja 250R > 2008 - 2012 Ninja 250R Tech Talk

Reply
 
Thread Tools
Old September 6th, 2016, 05:24 AM   #1
jc462
ninjette.org newbie
 
Name: Jim
Location: NE
Join Date: Jul 2016

Motorcycle(s): 250 and R6 track

Posts: 7
Wheel weight reduction - Help

I have seen various posts referring to wheels that were lightened. From what I can gather it seems like people have the rims machined in some manner.

Does anyone have additional information on this procedure, e.g. how much weight can be removed, any safety issues, a recommendation on where to have this done?

My ninja does exclusive racing and track day duty for both my son and myself.

Iím old and fat and need all the help I can get plus Iím the only 250 in the field running against all 300ís.

Thanks
jc462 is offline   Reply With Quote




Old September 6th, 2016, 06:40 AM   #2
adouglas
Cat herder
 
adouglas's Avatar
 
Name: Gort
Location: A secret lair which, being secret, has an undisclosed location
Join Date: May 2009

Motorcycle(s): 2012 Triumph Street Triple R (street), 2006 Yamaha R6 (track)

Posts: A lot.
Blog Entries: 6
MOTM - Jul '18, Nov '16, Aug '14, May '13


__________________________________________________
I am NOT an adrenaline junkie, I'm a skill junkie. - csmith12

Nam et ipsa scientia potestas est.
Heri historia. Cras mysterium. Hodie donum est. Carpe diem.
adouglas is offline   Reply With Quote


Old September 6th, 2016, 07:46 AM   #3
SLOWn60
n00bie to wannabie
 
SLOWn60's Avatar
 
Name: Bill
Location: St Ives, BC (Shuswap Lake)
Join Date: Sep 2015

Motorcycle(s): 2012 250R (Red), 2005 VFR800A (Red), CRF450X (Red), 2012 F800GS (Wants to be Red!)

Posts: A lot.
MOTM - Nov '15
As an old & fat rider myself; the safest, most cost/benefit results will be achieved if you remove the wheels, grab a wheel in each hand and raise them above your head. Do that for 3 sets of 10 every day. For even greater results: a little duct tape applied to the lips just before meals is extremely effective to reduce lap times!
__________________________________________________
The Smart Money: #1 - ATGATT, #2 - Training (machine skills and survival skills), #3 - The bike; whatever floats yer boat with the money you have left over
SLOWn60 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 6th, 2016, 08:18 AM   #4
JohnnyBravo
Certifiable nontundrum
 
JohnnyBravo's Avatar
 
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013

Motorcycle(s): 2013 SE NINJA 300

Posts: Too much.
MOTM - Sep '13, Sep '16
I've only seen the store bought kind
__________________________________________________
JohnnyBravo is offline   Reply With Quote


Old September 6th, 2016, 08:23 AM   #5
cbinker
Track Clown
 
cbinker's Avatar
 
Name: Chris
Location: Kingman, AZ
Join Date: May 2012

Motorcycle(s): '08 250R, '15 TTR-125, SV650 Racer

Posts: A lot.
MOTM - Sep '15
eat more salads.
__________________________________________________

TEAM ALFALFA
Unregistered swallows.
cbinker is offline   Reply With Quote


Old September 6th, 2016, 06:22 PM   #6
jc462
ninjette.org newbie
 
Name: Jim
Location: NE
Join Date: Jul 2016

Motorcycle(s): 250 and R6 track

Posts: 7
Hahahahaha

I knew I'd open myself up to the "Hey dude visit the salad bar once in a blue moon" response.

I'm tryin for sure...was 216lbs down to 190ish and still going - I get it this will make the biggest difference.

Put the bike on a weight loss program as well - just wondering about the wheel thing as that is probably the most effective place to reduce weight if possible.
jc462 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 6th, 2016, 07:04 PM   #7
SLOWn60
n00bie to wannabie
 
SLOWn60's Avatar
 
Name: Bill
Location: St Ives, BC (Shuswap Lake)
Join Date: Sep 2015

Motorcycle(s): 2012 250R (Red), 2005 VFR800A (Red), CRF450X (Red), 2012 F800GS (Wants to be Red!)

Posts: A lot.
MOTM - Nov '15
Quote:
Originally Posted by jc462 View Post
Hahahahaha

I knew I'd open myself up to the "Hey dude visit the salad bar once in a blue moon" response.

I'm tryin for sure...was 216lbs down to 190ish and still going - I get it this will make the biggest difference.

Put the bike on a weight loss program as well - just wondering about the wheel thing as that is probably the most effective place to reduce weight if possible.
In all seriousness; you do not want a wheel failure. I'm assuming you and your son race for shits & giggles. The bikes are designed for a typical rider and you & I are on the wrong side of the bell curve! The benefits of wanting to reduce unsprung, rotational forces by shaving unknown metallurgical, structural material from wheels cast in Indonesia should be considered carefully in the context of a weekend warrior! My (unwanted lol!) 2 cents!
It is very possible you might crack the wheel and your son disintegrates it!
__________________________________________________
The Smart Money: #1 - ATGATT, #2 - Training (machine skills and survival skills), #3 - The bike; whatever floats yer boat with the money you have left over
SLOWn60 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 6th, 2016, 07:05 PM   #8
Motofool
Daily Ninjette rider
 
Motofool's Avatar
 
Name: Hernan
Location: Florida
Join Date: Mar 2011

Motorcycle(s): 2007 Ninja 250

Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
Cool

Quote:
Originally Posted by jc462 View Post
......... Put the bike on a weight loss program as well - just wondering about the wheel thing as that is probably the most effective place to reduce weight if possible.
Please see this:
https://www.ninjette.org/forums/showthread.php?t=117501

There is no much weight that can be reduced from the wheel without affecting its strength.
The smallest profile of tire will help with both, lineal and rotational inertia.
__________________________________________________
Motofool
.................................Never ride faster than your guardian angel can fly
"Mankind is composed of two sorts of men ó those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - Josť MartŪ
Motofool is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 6th, 2016, 07:33 PM   #9
jc462
ninjette.org newbie
 
Name: Jim
Location: NE
Join Date: Jul 2016

Motorcycle(s): 250 and R6 track

Posts: 7
Thanks for the responses - Points taken on safety which is why I was asking.

I definitely race for fun, my son is 14 and is learning more and more each time he throws a leg over a bike - super cool to watch.

I definitely checked out this thread (multiple times).

Quote:
Originally Posted by Motofool View Post
I've done many of the usual things, e.g. exhaust (full area P), lightweight battery, ceramic wheel bearings, 415 chain and sprockets, speedo cable removal (with cool replacement spacer from DC dude), clip ons, front fender removal.

Investigating aluminum fairing stay and replacement gauge, lightweight brake rotor, fan removal, key removal, switches and housing removal and any other stuff I can learn about.

I wonder if wheels from another bike like RS125 could work somehow.
jc462 is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 6th, 2016, 07:44 PM   #10
JohnnyBravo
Certifiable nontundrum
 
JohnnyBravo's Avatar
 
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013

Motorcycle(s): 2013 SE NINJA 300

Posts: Too much.
MOTM - Sep '13, Sep '16
Ain't much weight to shave from the bikes, but it can be done... Always safety first though
__________________________________________________
JohnnyBravo is offline   Reply With Quote


Old September 6th, 2016, 09:17 PM   #11
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Good riding technique will swamp out small weight reductions in a hurry. I bet the time spent practicing on a track will be more important than the same amount of time spent trimming a little weight off the bike.
Triple Jim is offline   Reply With Quote


3 out of 3 members found this post helpful.
Old September 7th, 2016, 05:25 AM   #12
jc462
ninjette.org newbie
 
Name: Jim
Location: NE
Join Date: Jul 2016

Motorcycle(s): 250 and R6 track

Posts: 7
Quote:
Originally Posted by Triple Jim View Post
Good riding technique will swamp out small weight reductions in a hurry. I bet the time spent practicing on a track will be more important than the same amount of time spent trimming a little weight off the bike.

True dat. Definitely learning corner speed and momentum with this machine. I love to study riding - been to Corner spin, YCRS (3x) and CSS (levels 1 - 4).

Some folks are naturally good - I on the other hand need to work much harder to achieve a portion of a really talented riders skills. Never stop learning and tying to improve.

That being said racers are always looking to shave off a few ounces where ever they can.

This season a racing buddy bought a sprocket from a guy in the paddock - the next day the guy (another racer) came to him and said he forgot the thing had titanium hardware that he wanted back.
jc462 is offline   Reply With Quote


Old September 7th, 2016, 06:11 AM   #13
choneofakind
Where's my R6?!?!?!
 
choneofakind's Avatar
 
Name: Chris
Location: Western NC
Join Date: Feb 2011

Motorcycle(s): None anymore

Posts: Too much.
MOTM - Feb '13, Feb '14
In all seriousness though, check out various race tire weights and put that into your decision.

If you're going to be buying tires anyway, might as well get a set that can drop some weight from the outside of the wheel (the spot where mass with have the most effect on rotational inertia).
__________________________________________________
My ninjette may have fallen off the ugly tree, but I think she's beautiful
Leathers are hottt. Buy some and wear them every time!!!
I am slower than a herd of turtles stampeding through peanut butter.
choneofakind is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 7th, 2016, 11:20 AM   #14
subxero
dirty boy
 
subxero's Avatar
 
Name: Joe
Location: Johnstown, PA
Join Date: Sep 2012

Motorcycle(s): I don't even know anymore??

Posts: A lot.
MOTM - Apr '14
Weight reduction is very often a gotta pay to play kind of thing.

Some old threads from racers that cut some serious weight but they are not leaving any stone unturned. We are talking grinding and cutting any extra metal from frame tabs, losing ones that are not 100% necessary, doing smaller chain conversions, drilling things out, LiPo battery, among lots of other tricks, most of that stuff isn't that expensive. Once you start milking oz's here and there with Ti bits it starts to get pricy.

You want lighter wheels... buy a set of lighter race wheels, anywhere from $1500 - $4k for the crazy stuff.
__________________________________________________
I love the smell of burning pre-mix in the morning

I don't think I'm a lot dumber than you thought that I think that I thought I was once.
subxero is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 7th, 2016, 12:02 PM   #15
adouglas
Cat herder
 
adouglas's Avatar
 
Name: Gort
Location: A secret lair which, being secret, has an undisclosed location
Join Date: May 2009

Motorcycle(s): 2012 Triumph Street Triple R (street), 2006 Yamaha R6 (track)

Posts: A lot.
Blog Entries: 6
MOTM - Jul '18, Nov '16, Aug '14, May '13
Quote:
Originally Posted by jc462 View Post
plus Iím the only 250 in the field running against all 300ís.

Thanks
So sell the 250 and get a 300. It'll cost you less than trying to lighten the 250 enough to compete.

I echo what others said. Have you considered liposuction or lat band surgery?

Unsprung weight/rotating mass reduction has a big effect, but look at cost/benefit. There's a lot of room for weight savings before you start carving up mission-critical components willy-nilly.

A smallest-possible lithium battery will save you a lot of weight... ripping the wiring harness apart and chucking all but the essentials, ditto. Rig a keyswitch eliminator and save a couple more pounds. And none of those cost anywhere near what dedicated ultralight race wheels do.
__________________________________________________
I am NOT an adrenaline junkie, I'm a skill junkie. - csmith12

Nam et ipsa scientia potestas est.
Heri historia. Cras mysterium. Hodie donum est. Carpe diem.
adouglas is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 8th, 2016, 05:36 AM   #16
jc462
ninjette.org newbie
 
Name: Jim
Location: NE
Join Date: Jul 2016

Motorcycle(s): 250 and R6 track

Posts: 7
Quote:
Originally Posted by subxero View Post
Weight reduction is very often a gotta pay to play kind of thing.
I hear ya on that one - hence the ask on machining the wheels.

Quote:
Originally Posted by adouglas View Post
So sell the 250 and get a 300. It'll cost you less than trying to lighten the 250 enough to compete.

Unsprung weight/rotating mass reduction has a big effect, but look at cost/benefit. There's a lot of room for weight savings before you start carving up mission-critical components willy-nilly.

A smallest-possible lithium battery will save you a lot of weight... ripping the wiring harness apart and chucking all but the essentials, ditto. Rig a keyswitch eliminator and save a couple more pounds. And none of those cost anywhere near what dedicated ultralight race wheels do.
Thought about the 300 - probably would make more sense...problem is I don't have an abundance of sense sometimes.

Seriously - the 250 is really my sons bike that's why I am not willy-nilly and I check everything out before I make any move. I raced it this year in addition to my R6 to put it under some pressure and work out kinks. He does track days on it when he's not riding dirt or kart tracks.

This bike is a stepping stone for him if he decides to continue on.

I've done several things to the bike, e.g. harvested a lithium battery from one of my other race bikes, chain conversion etc...

Really poking around at options now that I'm in the off-season from racing.

I appreciate all of the responses and good advice - especially the motivating words folks offer around the rider weight reduction modification
jc462 is offline   Reply With Quote


Old September 8th, 2016, 07:01 AM   #17
RacinNinja
Vintage Screwball
 
RacinNinja's Avatar
 
Name: B
Location: Washington
Join Date: Feb 2016

Motorcycle(s): 2011 Ninja 250, 2014 FZ09

Posts: A lot.
MOTM - Mar '16
Don't machine the wheels. Don't worry about weight. The small amount you'll lose even with expensive Marchesini's won't do much for you. They won't keep with Ninja 300's or KTM 390's or Yamaha R3's no matter what you do. Those have at least 10 HP on the Ninja 250. You can keep up in the corners but will get dogged in the straights.

Instead, get good tires, good suspension and then focus on rider skills. Don't race to win, race to have fun and learn! Race the lap timer.
__________________________________________________
Goin' fast on slow bikes!

RacinNinja is offline   Reply With Quote


3 out of 3 members found this post helpful.
Old September 8th, 2016, 07:03 AM   #18
JohnnyBravo
Certifiable nontundrum
 
JohnnyBravo's Avatar
 
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013

Motorcycle(s): 2013 SE NINJA 300

Posts: Too much.
MOTM - Sep '13, Sep '16
Just have fun man, that's what it's all about
__________________________________________________
JohnnyBravo is offline   Reply With Quote


Old September 8th, 2016, 08:58 AM   #19
Motofool
Daily Ninjette rider
 
Motofool's Avatar
 
Name: Hernan
Location: Florida
Join Date: Mar 2011

Motorcycle(s): 2007 Ninja 250

Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
Cool

Quote:
Originally Posted by jc462 View Post
......... Really poking around at options now that I'm in the off-season from racing.......
Quote:
Originally Posted by choneofakind View Post
In all seriousness though, check out various race tire weights and put that into your decision.

If you're going to be buying tires anyway, might as well get a set that can drop some weight from the outside of the wheel (the spot where mass with have the most effect on rotational inertia).
Weight saved in tires provides a double gain for both acceleration and braking.

Besides the force (along the chain) necessary to lineally accelerate the mass of both tires (rotating or not, just the mass or weight), an additional torque (radius of sprocket times force also along the chain) is needed to overcome the moment of inertia (angular mass or rotational inertia) of both tires while they change speed.

Force along the chain is limited by the torque of the engine, which has a max.
For that reason, heavier tires will consume more of that torque, slowing the processes of acceleration and braking down.
Discs brakes are superior to drum brakes in that aspect.

Please see:
http://hpwizard.com/rotational-inertia.html

https://en.wikipedia.org/wiki/Moment_of_inertia

As @choneofakind has explained, for two more or less similar wheel-tire combinations, the mass farther from the center of rotation is the more important to reduce resistance to acceleration and deceleration as much as possible.
In that sense, 16" wheels and tires are better than 17" ones.

__________________________________________________
Motofool
.................................Never ride faster than your guardian angel can fly
"Mankind is composed of two sorts of men ó those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - Josť MartŪ
Motofool is offline   Reply With Quote


Old September 8th, 2016, 10:14 AM   #20
csmith12
The Corner Whisperer
 
csmith12's Avatar
 
Name: Chris (aka Reactor)
Location: Northern KY
Join Date: May 2011

Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track)

Posts: Too much.
MOTY 2015, MOTM - Nov '12, Nov '13
One of the fastest 250 riders I know is 300+lbs. ijs.....
csmith12 is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 8th, 2016, 10:33 AM   #21
RacinNinja
Vintage Screwball
 
RacinNinja's Avatar
 
Name: B
Location: Washington
Join Date: Feb 2016

Motorcycle(s): 2011 Ninja 250, 2014 FZ09

Posts: A lot.
MOTM - Mar '16
Quote:
Originally Posted by csmith12 View Post
One of the fastest 250 riders I know is 300+lbs. ijs.....
Momentum riding.

The less you slow down, the less you have to accelerate.
__________________________________________________
Goin' fast on slow bikes!

RacinNinja is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 8th, 2016, 12:43 PM   #22
SLOWn60
n00bie to wannabie
 
SLOWn60's Avatar
 
Name: Bill
Location: St Ives, BC (Shuswap Lake)
Join Date: Sep 2015

Motorcycle(s): 2012 250R (Red), 2005 VFR800A (Red), CRF450X (Red), 2012 F800GS (Wants to be Red!)

Posts: A lot.
MOTM - Nov '15
Quote:
Originally Posted by csmith12 View Post
One of the fastest 250 riders I know is 300+lbs. ijs.....
Ask Misti about Stuman! He's not on a 250 and he's not 300 lbs but he's a big man and holy holy; he's fast!!!!
__________________________________________________
The Smart Money: #1 - ATGATT, #2 - Training (machine skills and survival skills), #3 - The bike; whatever floats yer boat with the money you have left over
SLOWn60 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 9th, 2016, 05:43 PM   #23
NinJim
ninjette.org member
 
Name: Jim
Location: Utah
Join Date: Apr 2016

Motorcycle(s): Ninja250-3x; CBR600 & R6 (track bikes); lots of dirt stuff

Posts: 25
Change bikes - Go to a real GP bike

You're missing a real easy way to have the best.

Buy a MotoGP 125cc bike. New, they were $10k, with spares $20k. Weight 155 pounds, 40hp.

You can pick one up with tons of spares: pistons, cylinders, gear sets for the six-speed trans, etc. Prices seem to be in the $2-4k range, which is the same price as a used Ninja. But you get a sophisticated race bike with nothing that needs to be done to it. It will run with the Ninjas, but brakes and turns for real. If dragging knees is important to you (seems to be on this forum), this bike will let you drag knees, boots and elbows.

That's what I did for my boy at that age. I told him, when that bike had taught him everything it could, he would know exactly what bike to race. But he surprised me, by staying with it until he quit racing. (job and family)

It was really fun watching him stuff 600's in turns and out braking them by a mile. But the best thing was putting it back in the truck - no ramp! Lift up the front, place on tailgate, lift up back, done.

Just some thoughts,
cheers,
NinJim is offline   Reply With Quote


3 out of 3 members found this post helpful.
Old September 12th, 2016, 10:36 AM   #24
bruce71198
ninjette.org sage
 
bruce71198's Avatar
 
Name: bruce
Location: northern illinois
Join Date: Jan 2012

Motorcycle(s): Race bikes:08 Ninja 250,11 R6,16 ZX6,SV650.3 HD-1947,2-2003,2010. 1946 Indian and a lot of dirt bikes.2

Posts: 995
I'm a big fan of masking my riding inequities with horsepower....
bruce71198 is offline   Reply With Quote


1 out of 1 members found this post helpful.
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
300 weight reduction Tigerpaw 2013 - 2017 Ninja 300 Tech Talk 36 February 18th, 2014 02:58 PM
Weight reduction performance improvement ex250 azian4lifz 1986 - 2007 Ninja 250R Tech Talk 19 October 18th, 2013 10:41 AM
Wheel weight came off.. KawiKid860 General Motorcycling Discussion 2 November 16th, 2011 12:54 AM
[kropotkin thinks...] - Ducatis To Get 3kg Weight Reduction Ninjette Newsbot Motorcycling News 0 May 16th, 2010 04:21 PM
[crash.net - WSBK] - FIM agree twin-cylinder weight reduction Ninjette Newsbot Motorcycling News 0 May 16th, 2010 11:20 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Motorcycle Safety Foundation

All times are GMT -7. The time now is 09:15 PM.


remote server monitor
Powered by vBulletin®
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Except where otherwise noted, all site contents are © Copyright 2019 ninjette.org, All rights reserved.