How will a drop of 80-100 pounds affect FJR handling?

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ADMINS: Feel free to move this thread to another area if needed.

Situation: I am seriously considering lap band or gastric bypass surgery for medical reasons. I am not asking for advice about the procedures or people's experiences with the surgeries, but accept good natured ribbing or advice. I am serious enough to switch insurance policies to a more surgery-friendly variety. I figure the savings in not having to buy super-sized clothing or super-sized meals may pay for the surgery alone. As I am starting to replace or buy gear for next season, and consider custom suspension on my KLR650, this alone would be a considerable savings. I have a 2006A with GP suspension set for a guy @340 with gear and occasional 2-up riding. The suspension works wonderfully. My question is moto and FJR specific:

What can I expect to happen with an 80-100 pound weight loss? Aside from resetting SAG, (or even having the suspension redone by GPS next winter -- I hope not as that would be pricey) what should I expect in terms of the ride? Will I have to change the way I ride? Anybody have experience with this situation or expertise in suspension/riding that could advise me? What am I not considering? Even as I write this I suspect I would get better gas mileage (for example).

Anybody want to speculate on what this might entail off-road as well?

 
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I am down almost 140lbs from my prime. You will notice a big change in how nimble the bike feels and it will be quicker. I think 7-10 lbs is equal to 1 horsepower. On the KLR it won't dive as bad on breaking and the HP increase will be more noticeable. The lack of girth makes it a lot easier to move around on the bike and standing on the pegs on the KLR is easier and lowers the COG for better handleing. On the KLR all I did to the suspension was to add 1/2 inch spacers to the front springs and heavier fork oil and on the rear I made a shim for the rear spring. MM2 has my old KLR and is not a small person. He seems satisfied with the suspension for general use. Someday he is going to return it to its proper home :rolleyes:

 
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Not sure about the suspension changes you might need, although I would predict a noticable change, but the decision to make your life healthier as you have described above has to be a difficult one. I wish you the best of luck & success if your surgery is a go.

 
Subject line indicates a FJR-specific thread; moving to correct forum.

As to your question: dropping 80-100 lbs will make your current suspension settings (assuming they are correct for the current weight) seem quite harsh, particularly riding over bumps/railroad tracks, etc.

After the weight loss, you will want to consider re-springing the rear shock (ASSuming you have an aftermarket, obviously), as well as the front. The GP Suspension route would be ideal, and a good "reward" for the successful weight loss.

Good luck!

 
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Shiny,

I'm not sure how loss of weight will affect the bike's ride but have some suggestions.

1- Eliminate all the High Fructose Corn Syrup intake from your food supply. I did this and lost about 4" around the middle. Here is a link on the details:

https://www.thefitshack.com/2007/03/15/what...ad-for-my-body/

2- Wish you all the Best in this endeavor and a Happy Healthy New Year!

 
Shiny, Best of Luck to You and I'm Supporting You, whatever decision you make! I personally hate to see my friends go for elective surgery, because I'm scared something could go wrong; but I know you're in the medical field and have researched!

 
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My biggest concern is your having to abdicate your position as "Los Robustos MC número de miembros, de dos El Grande "

You go losing that much weight and your membership (and commitment to an ancient and revered society) is seriously compromised.

Best of luck in your endeavor.

'Howie

 
My biggest concern is your having to abdicate your position as "Los Robustos MC número de miembros, de dos El Grande "
You go losing that much weight and your membership (and commitment to an ancient and revered society) is seriously compromised.

Best of luck in your endeavor.

'Howie
El Pinche Pescado Malo hablos la Verdad! You lose 100 lbs.: johnny80s and I are kicking your ass out of Los Robustos M/C!!!

 
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My biggest concern is your having to abdicate your position as "Los Robustos MC número de miembros, de dos El Grande "
You go losing that much weight and your membership (and commitment to an ancient and revered society) is seriously compromised.

Best of luck in your endeavor.

'Howie
El Pinche Pescado Malo hablos la Verdad! You lose 100 lbs.: johnny80s and I are kicking your ass out of Los Robustos M/C!!!
Shiney is in for good. He is a brother through and through. If he does lose that much weight he won't want to ride with us and eat all that crap anymore. I am with you Shiney I am trying to lose 40 lbs myself.

 
My biggest concern is your having to abdicate your position as "Los Robustos MC número de miembros, de dos El Grande "
You go losing that much weight and your membership (and commitment to an ancient and revered society) is seriously compromised.

Best of luck in your endeavor.

'Howie
El Pinche Pescado Malo hablos la Verdad! You lose 100 lbs.: johnny80s and I are kicking your ass out of Los Robustos M/C!!!
Shiney is in for good. He is a brother through and through. If he does lose that much weight he won't want to ride with us and eat all that crap anymore. I am with you Shiney I am trying to lose 40 lbs myself.
Is the World as We Know It coming to an end? Is Doomsday coming on The Winter Solstice? Stop this damn heresy right now!

 
My biggest concern is your having to abdicate your position as "Los Robustos MC número de miembros, de dos El Grande "
You go losing that much weight and your membership (and commitment to an ancient and revered society) is seriously compromised.

Best of luck in your endeavor.

'Howie
El Pinche Pescado Malo hablos la Verdad! You lose 100 lbs.: johnny80s and I are kicking your ass out of Los Robustos M/C!!!
Shiney is in for good. He is a brother through and through. If he does lose that much weight he won't want to ride with us and eat all that crap anymore. I am with you Shiney I am trying to lose 40 lbs myself.
Is the World as We Know It coming to an end? Is Doomsday coming on The Winter Solstice? Stop this damn heresy right now!
I'm with you Don. I sincerely believe the weight you are is what's right for you.

When I was in my late teens, through my thirties, my weight always hovered around 240, whether I ate like a pig, excerised my ass off or fasted like a hermit.

Now in my 50s, my weight is around 270. Doesn't matter if I eat healthy, eat roadkill, exercise my ass off or don't move from my La-Z-Boy for weeks on end.

The only time my weight has varied in the past 30 years is when my only nutrition was an intravenous drip for 6 weeks with the only outlet being a catheter. Even then, my weight only dropped about 15 pounds! :blink:

That's pretty much when I became convinced that unless you're eating a dozen donuts 5 times a day, your body finds its own weight. I mean, c'mon, nothing but fluids for 6 friggin weeks and I lose only 15 pounds? Hell, that's barely more than a good bowel movement and bladder dump!

That all being said, I :clapping: Shiney for wanting to change his lifestyle, because that's what it is...a lifestyle change, not just a weight change.

 
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I think 7-10 lbs is equal to 1 horsepower.
It's not a linear relationship. As you reduce weight, the amount of reduction necessary for a 1hp "gain" is also reduced. I'm pretty sure I didn't mess up my thought process and math...

Code:
[relative HP "gain"] = (([initial weight] * [actual HP]) / [new weight]) - [actual HP]
Use that to calculate how much of a change in Hp it will feel like you get from changing the overall weight of bike + rider + gear, relative to how the actual amount of HP felt to you at the original weight.

For a 340lb rider on an FJR, losing 100lbs would feel the same as if they just added ~14hp (at the wheel) to the bike without losing weight. Of course, this apparent HP gain is diminished with higher speeds, because air resistance doesn't care how much you weigh; you're still fighting the same amount of air resistance with the same amount of HP.

 
I think 7-10 lbs is equal to 1 horsepower.
It's not a linear relationship. As you reduce weight, the amount of reduction necessary for a 1hp "gain" is also reduced. I'm pretty sure I didn't mess up my thought process and math...

Code:
[relative HP "gain"] = (([initial weight] * [actual HP]) / [new weight]) - [actual HP]
Use that to calculate how much of a change in Hp it will feel like you get from changing the overall weight of bike + rider + gear, relative to how the actual amount of HP felt to you at the original weight.

For a 340lb rider on an FJR, losing 100lbs would feel the same as if they just added ~14hp (at the wheel) to the bike without losing weight. Of course, this apparent HP gain is diminished with higher speeds, because air resistance doesn't care how much you weigh; you're still fighting the same amount of air resistance with the same amount of HP.
So basically, you can't go any faster than you do now, but you'll be able to get to that upper limit quicker. Right???

 
I think 7-10 lbs is equal to 1 horsepower.
It's not a linear relationship. As you reduce weight, the amount of reduction necessary for a 1hp "gain" is also reduced. I'm pretty sure I didn't mess up my thought process and math...

Code:
[relative HP "gain"] = (([initial weight] * [actual HP]) / [new weight]) - [actual HP]
Use that to calculate how much of a change in Hp it will feel like you get from changing the overall weight of bike + rider + gear, relative to how the actual amount of HP felt to you at the original weight.

For a 340lb rider on an FJR, losing 100lbs would feel the same as if they just added ~14hp (at the wheel) to the bike without losing weight. Of course, this apparent HP gain is diminished with higher speeds, because air resistance doesn't care how much you weigh; you're still fighting the same amount of air resistance with the same amount of HP.
Thanks Pickles, I'm going to have to save that equation for future reference. That makes more sense than just continuing to make HP gains indefinately!

Warchild: I have the GP front and rear done two years ago during the group buy. I'm afraid you are right that if I lost that much weight I'll have to have both ends of the suspension done.

Howie, I agree to a point with you. However, I haven't seen 270 lbs since Junior High. I worked out in college twice a day for 4 hours total in the Gym, swimming, running, weights, etc. and never got under 290.

Thanks for the support Johnny and guys. My biggest concern is not giving up food, amazingly enough, it's Diet Coke. I am addicted.

I also need to see the doctor to ensure I would be totally healed and able to eat (small portions -- sorry el jefe) Mexican Food by November. If the answer is no or "maybe" I will wait until 2011. I am going on that trip to Copper canyon.

Follow-up question to the collective: Would the ride be so harsh, do you think, that the FJR would be dangerous to ride? Would the softest settings on the Penske shock and fork be "good enough"? I should probably shoot a PM off to Dave at GP Suspension if I go through with this.

At least my **** would be bigger (perspective is everything dontcha know?).

 
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Shiney, You and i need to talk.

I have been thinking heavily about this as well.

I see these signs for 1 800 Lap Bands and i get thinking about my options as well. My only problem is that the insurance i have will not pay for it, And i cannot just switch to another carrier because of my pre-existing conditions. <_<

So, This leaves me paying for it out of pocket 100% and i just don't have that kind of money. I am open to your options.

 
I think 7-10 lbs is equal to 1 horsepower.
It's not a linear relationship. As you reduce weight, the amount of reduction necessary for a 1hp "gain" is also reduced. I'm pretty sure I didn't mess up my thought process and math...

Code:
[relative HP "gain"] = (([initial weight] * [actual HP]) / [new weight]) - [actual HP]
Use that to calculate how much of a change in Hp it will feel like you get from changing the overall weight of bike + rider + gear, relative to how the actual amount of HP felt to you at the original weight.

For a 340lb rider on an FJR, losing 100lbs would feel the same as if they just added ~14hp (at the wheel) to the bike without losing weight. Of course, this apparent HP gain is diminished with higher speeds, because air resistance doesn't care how much you weigh; you're still fighting the same amount of air resistance with the same amount of HP.

Air resistance would indeed be reduced because of the smaller silhouette presented due to weight loss.

 

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