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weight reduction

14K views 33 replies 20 participants last post by  Vger1 
#1 ·
I'm new to the bike world and am realizing that on a bike every pound counts (especially on a 250). I'm wondering what are some ways that I can reduce the weight of an 08 250. I plan on getting an area P exhaust for the weight savings and the sound. I saw in a different post about taking off the rear brake but I wont be doing that.
 
#5 ·
definetely not looking at a higher cc bike, I'm just looking to make the most out of this bike. I'm more interested in doing things that will increase the bike's efficiency and MPG as this is the main reason I bought the bike. I figure if I could drop a few pounds off the bike without compromising safety than I would like to do it.
 
#7 ·
I read a post on here about replacing the battery with a smaller type to save some weight. You could search that up.

If you are looking to "to increase the bike efficiency and MPG" then you could consider regearing for lower rpms.

The bike already gets over 50 MPG in the worst examples...not sure how you are going to beat on that with a couple of pounds off the bike...In most cases, like others have posted, the rider is the one carrying "optional" weight.
 
#29 ·
Bad idea; best braking is a combination of both front and rear.. yes, the front is responsible for 70-80% of your braking, but the rear WILL help slow you down faster in conjunction with the front.

Adam-

You are on the right track. weight reduction is the fastest, easiest way to increase yur bike's performance, both it's acceleration ad braking, and also its suspension's ability to do it's job.

First and most obvious advice: ignore the dummies on this board who'll question why you want to do this or that. Like the previous post^. they contribute nothing to the discussion except to make themselves look ignorant.

As for weight reduction, yes, you are correct; the less power a bike has the more important weight reduction becomes and the more noticable the gains. Your 250 is perfect for a weight reduction program.

first, replace the stock header and pipe with an AP full system. Saves alot of weight and really increases the bikes hi-end performance. This is a must.

Second, reduce your rotating mass. Standard theory is that 1 lb of rotating mass = 7 lbs regular weight. best place to start is an aluminum rear sprocket (while you are at it change your gearing to 15/43, so you'll need a 15t front too). Next, if you are ambititous, take your rear rotor to a machine shop and have then drill it out as much as possible. there's easily 3/4 lb of weight to be lost there. With the alum sprocket and drilled rotor you'll notice better acceleration and braking and better turn in and rear suspension compliance.

Third, believe it or not, your tire choice. tire weight is the least appreciated aspect of weight reduction, yet it can be the most critical. It's rotating mass, and it's mass in the most critical area - rim weight - where it's effect is most pronounced. For example, a 120/70/17 bt-014 front tire weighs 3.8 kgs, while the Dunlop 208 front weighs 4.8 kgs. That means that the bt014 is 2.2 lbs lighter than the same size dunlop. Thats 2.2 lbs, at the farthest pint frm the axle, and thus the most pronounced, that the engine has to accelerate from a dead stop, the brakes must stop, and the suspension must keep firmly planted on the pavement. People spend $3500 on carbon fiber wheels to get similar weight savings in rim weight. You can do it for nothing by choosing the right tires.

My 250 came with the Dunlop GT501s. good, sticky tires, but heavy. As soon as i burn them off i'm going to either te bridgestone bt45s or the bt90s. Much lighter tires.

In addition to the above, you can replace the hardware (bolts & nuts) with titanium racing units - expensive, but it will drop at least a few pounds. Also; in addition to tires you can go with lighter wheels; also expensive, but a big improvement. Finally - instead of a 100% aluminum sprocket (which will wear quickly), I'd go with a twin-ring unit - the outer edge & teeth are titanium and the rest is aluminum. Very light, but MUCH more wear-resistant than aluminum alone.

You would be a tard to take off the rear brake. I use my rear brake more then the front. I would rather lock the rear then the front.
This is good advice... on a dirt bike, when off road. On a street bike, on pavement, you're begging for a high-side. I ride both on & off road, and I know what I'm talking about here.

Yes, you can lock the rear and still use the front and still come to a stop OK but many people, especially new riders, will panic and release the rear to reapply if it gets locked by reflex.
Very true. The answer is to practice in a safe area under controlled conditions to learn your bike/tires' limits before reaching lockup. Do it enough so it's second nature. In an emergency stop, your muscle memory will kick in.
 
#10 · (Edited)
Adam-

You are on the right track. weight reduction is the fastest, easiest way to increase yur bike's performance, both it's acceleration ad braking, and also its suspension's ability to do it's job.

First and most obvious advice: ignore the dummies on this board who'll question why you want to do this or that. Like the previous post^. they contribute nothing to the discussion except to make themselves look ignorant.

As for weight reduction, yes, you are correct; the less power a bike has the more important weight reduction becomes and the more noticable the gains. Your 250 is perfect for a weight reduction program.

first, replace the stock header and pipe with an AP full system. Saves alot of weight and really increases the bikes hi-end performance. This is a must.

Second, reduce your rotating mass. Standard theory is that 1 lb of rotating mass = 7 lbs regular weight. best place to start is an aluminum rear sprocket (while you are at it change your gearing to 15/43, so you'll need a 15t front too). Next, if you are ambititous, take your rear rotor to a machine shop and have then drill it out as much as possible. there's easily 3/4 lb of weight to be lost there. With the alum sprocket and drilled rotor you'll notice better acceleration and braking and better turn in and rear suspension compliance.

Third, believe it or not, your tire choice. tire weight is the least appreciated aspect of weight reduction, yet it can be the most critical. It's rotating mass, and it's mass in the most critical area - rim weight - where it's effect is most pronounced. For example, a 120/70/17 bt-014 front tire weighs 3.8 kgs, while the Dunlop 208 front weighs 4.8 kgs. That means that the bt014 is 2.2 lbs lighter than the same size dunlop. Thats 2.2 lbs, at the farthest pint frm the axle, and thus the most pronounced, that the engine has to accelerate from a dead stop, the brakes must stop, and the suspension must keep firmly planted on the pavement. People spend $3500 on carbon fiber wheels to get similar weight savings in rim weight. You can do it for nothing by choosing the right tires.

My 250 came with the Dunlop GT501s. good, sticky tires, but heavy. As soon as i burn them off i'm going to either te bridgestone bt45s or the bt90s. Much lighter tires.
 
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#13 ·
You would be a tard to take off the rear brake. I use my rear brake more then the front. I would rather lock the rear then the front.
:eek: Okay you're the first person I've ever heard say you'd rather lock the rear than the front. From what I've read, locking the rear brake causes fishtailing and eventually a highside. Anyone considering Jason's advice should look for a second opinion first.

There has even been some discussion regarding removing the rear brake (I can't remember which thread, but it was just a few days ago). Someone proposed removing the rear brake to reduce weight, and there were some who were adamant that it was a stupid idea, and some who agreed that it was okay. (Personally I would err on the side of safety and keep it on, but that's just me...)
 
#19 ·
remove the toolkit, thats a pound or two

oh and take a big sh** before you ride. thats another 2 lbs :D

i honestly dont think it would make a noticable difference unless you made drastic mods. yes a couple pounds here and there may increase mpg and maybe hp, i highly doubt you would actually feel it.
 
#20 ·
To those saying you will highside if you loose the rear brake... I agree its better to lock the rear...

If you are calm enough to just clamp down on the rear brake and then slow using the front then you will come out of it just fine (unless you are going into a corner)...

One guy on here the other day talked about how when the locked the front within 1/4 of a second he was down...

You can ride with the rear locked, ever done it on a bicycle? Its not a fun feeling at speed but if you keep it locked and keep it straight you should be just fine...
 
#21 ·
An Area P will definetly make your ride more enjoyable, any exhaust will.. And to get the max out of it you really should take it in to a dyno shop to get it tuned and jetted, to gain the max performance (Area P says it will work without a jet but it will benefit and most exhausts highly recommend it).

And to the MPG, the area P will reduce weight but I have heard it does cause a reduction in MPG, but I assume you could counter this to some extent by going with a 15/43 gearing...
 
#24 ·
This must be some sort of karma ;)...

Check out my "incident" post...

Anyways...

I asked the question there but how do you know what amount of rear pressure is to much?

And I wasnt saying I'd rather use the rear then the front brake, just that I'd rather lock it up but I guess its really not that safe (atleast at higher speeds, see my thread for my low speed lock up).

Is it okay to give it a few pounds of down force, while panic stopping, if the majority of the force is on the front?

Lastly, have you guys found that habits like this (not slamming the rear) that are practiced many times in say a parking lot do help on the street in a panic situation or does your fear/shock take over and make you slam that rear, regardless?

Kind-of makes me rethink the recent post about rear brake removal ;), or wish my pegs were more like a harley (its easier to rest your feet on the peg/pad without having a toe right over the rear brake just waiting to be slammed in a panic situation).
 
#25 ·
This must be some sort of karma ;)...

Check out my "incident" post...

Anyways...

I asked the question there but how do you know what amount of rear pressure is to much?

And I wasnt saying I'd rather use the rear then the front brake, just that I'd rather lock it up but I guess its really not that safe (atleast at higher speeds, see my thread for my low speed lock up).

Is it okay to give it a few pounds of down force, while panic stopping, if the majority of the force is on the front?

Lastly, have you guys found that habits like this (not slamming the rear) that are practiced many times in say a parking lot do help on the street in a panic situation or does your fear/shock take over and make you slam that rear, regardless?
My MSF ridercoach advised us to use a parking lot and try braking from different speeds to figure out what is and isn't OK for YOU'RE specific bike once you get it. He recommended locking the rear on purpose and sliding it to a stop to see how it feels and to know what you can and can't do when the need for quick braking comes up. I know some are going to say "your MSF told you to purposely lock the rear!?" but to me it's better to figure out what your bike can and can't do in a closed controlled environment instead of out on the street.

Not sure how this differs from the adviced from others or saying this is the best but that's the information that was given to me. He didn't say to be doing speeds that fast though. Around 25 or less.
 
#26 ·
Did he recommend just feeling the rear or doing a full panic stop (hard on the front)?

It must be real hard on a full size bike to lock just the rear but even if you could I doubt you'd learn anything while doing it... What I would want to experiment with is the rear brakes limits while moderatly heavy on the front brake...
 
#31 ·
i'm going with a 15/41 sprocket combo.
i have an area p exhuast, pod filters, no kawasaki green emission system, all carb mods done.
a think the michelin pilots are the lightest tires for the 250. i wonder if a 120 on the rear tire would help.
i thnik the plastics are heavy. too bad there wasn't a naked or half naked option for the 250.
titanium hardware would be good.
 
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