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Discussion Starter · #1 ·
I recently tightened the chain on my bike but noticed riding around that it still felt like the chain was 'stretched' or loose. on acceleration/de-cel the front comes up and down as if it's the chain, not the suspension. Now I'm not sure anymore and think it might be the suspension.

I bought the 650r used and its been like this since i got it. it was also 'stunted' for some tv show so I guess now that I think about it, the front suspension might have been impacted by that.

with no one on the bike, the slack is a bit over one inch, so it should be snug when i'm sitting on it. i'll see if the ol lady can sit on the bike for me later tonight to confirm.

In the meantime, I'm rethinking that I should drop teh front end. It's not a supersport and its designed to be more 'soft' but i'm thinking one inch down from the forks should be enough to change teh geometry of the bike but not creating any riding risks.

Any suggestions/comments? I was thinking that loosening the bolts holding the forks one fork at a time should be the best way to do this.
 

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the joke is in your hand
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the chain has no bearing on the front suspension. it has little to no affect on the rear either unless it's too tight. no, you don't want the chain snug with someone on it. it should still have a good deal of slack.
if it doesn't then you're binding the shock in it's stroke and causing it to not work properly

no sure what you're problem is by your description but if your having front suspension issues it's not your chain.
 

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Discussion Starter · #3 ·
Well on the r1 and even the zx14 the nose would not rise and fall on acceleration or laying off the throttle. it doesn't feel like it is the suspension because it goes up/down a certain amount, the same way a loose chain will do it.

by lowering the front i want more weight shifted to the front, which will stiffen the suspension and most likely get rid of this front end raising/diving just by twisting the throttle one way or another. On my fz6 adn other non-supersports it did the same but i could easily tell that it was the suspension and the movement wasn't as easy.
 

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If you are talking about the Ninja 650R it sounds like it needs stiffer springs in front and the proper spec oil added to the correct level. Check the aftermarket or your dealer. I definitely would not mess with the suspension geometry. Your chain should be set to the smallest slack recommended in the owner's manual where the chain is tightest when you rotate the wheel. Excessive slack results in 'chain snatch' as you roll on/off the throttle. Also check the chain/sprockets for wear; you should not be able to pull the chain away from the teeth on the rear sprocket any distance.
 

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Yea dude the stock 650r suspension us crap. Look at doing a conversion or upgrade.

Sent from my DROIDX
 

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Make sure that you're checking the chain's slack in more than one spot. If it has tight spots, make sure to set the chain slack based on the tightest spot. Also, if it does have tight spots in the chain, you'll likely be needing a new chain and sprockets coming up.

New springs and oil are a pretty cheap solution to fixing up a sloppy front end (assuming nothing is actually broken). I put Sonic Springs in my SV. The owner is active on SVRider and helped me to pick out the correct spring for my weight and riding style. He was great to deal with and I can't recommend him enough.

Here is a spring rate calculator from his page: SonicSprings.com

If you have any questions email him. He's quick to reply and very helpful. If you do change the springs and oil, you might as well change the fork seals, especially if it was owned by a stunter.
 

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the joke is in your hand
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Well on the r1 and even the zx14 the nose would not rise and fall on acceleration or laying off the throttle. it doesn't feel like it is the suspension because it goes up/down a certain amount, the same way a loose chain will do it.

by lowering the front i want more weight shifted to the front, which will stiffen the suspension and most likely get rid of this front end raising/diving just by twisting the throttle one way or another. On my fz6 adn other non-supersports it did the same but i could easily tell that it was the suspension and the movement wasn't as easy.
it sure does come up. but you have a harder time noticing it because of their aggressive seating position.
 

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By the way, stunting had nothing to do with it. Considering those are damper rod forks, the worst that could happen is a blown fork seal.
 

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I keep my chains on the loose side, I'm just careful with alignment. They last a lot longer than keeping them tight.

But to your fluffy suspension issue, aren't those forks just damper rods? If they are, get some fork oil, some thick-walled PVC pipe and some metal pipe. The pipes should be similar in size to your springs. Change your fork oil. Cut a longer spacer out of PVC pipe. See if it makes a positive effect. Keep going until you're happy or can't cap the forks. When you find a good PVC length, re-cut your spacer with good metal pipe.

The idea is it flattens out the spring rate on the progressive rate springs and makes them more linear. Truth be told, real flat-rate springs are a better choice, but if you're hesitant to buy them for whatever reason, playing with spacers is sort of, "let's see if it fixes the problem" process.

If you ever use the brakes for anything other than slow and easy stops, raising the forks an inch in the triples will mean that you'll end up hitting the triple with the top of the fork legs.
 

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Discussion Starter · #10 ·
I look at this bike as a total beater and don't want to spend much money on it. I already put some $ into the brakes when it really didn't need it. I appreciate all the good information shared.

I'm mechanically inclined but not inclined to work on something that I haven't done before and suspension is just that. I was hoping for a simpler solution but it seems like its more work than its worth.

I googled around and the 650R does have the damper rods, but I'm still not sure what that means. I do know that its more than a few hundred bucks for a proper ungrade and I'm not even sure how long I want to keep this bike. The bike is 6-7 years old, can the fork oils lose their viscosity? I'm wondering if just swapping that out would help. Yeah, I know I'm still looking for a cheap/easy solution...sorry for being that way.
 

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I look at this bike as a total beater and don't want to spend much money on it. I already put some $ into the brakes when it really didn't need it. I appreciate all the good information shared.

I'm mechanically inclined but not inclined to work on something that I haven't done before and suspension is just that. I was hoping for a simpler solution but it seems like its more work than its worth.

I googled around and the 650R does have the damper rods, but I'm still not sure what that means. I do know that its more than a few hundred bucks for a proper ungrade and I'm not even sure how long I want to keep this bike. The bike is 6-7 years old, can the fork oils lose their viscosity? I'm wondering if just swapping that out would help. Yeah, I know I'm still looking for a cheap/easy solution...sorry for being that way.
Damper rod forks, dont have the cartridges as in cartridge forks, even though cartridge forks also have damperods.

Yes even though you have damper rod only forks you can stiffin them up, through oil viscosity and springs.
 

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When you pull the caps off the tubes and you get a good whiff of that old fork oil, you'll be happy you changed it.

The damper rod forks are super easy to work on, unless you're replacing the damper rod itself. I've heard the cartridge are easier, but I have no experience working on them myself.
 

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so it should be snug when i'm sitting on it.
No No it shouldn't, with you on the bike the chain in the middle of its run should have 10-20mm free play. If it is snug then it is limiting your suspension travel and you risk doing a lot of damage not only to chain but gearbox output bearings and the like. Or the chain will break rip the side out of you gearbox casings and lock the rear wheel if you are lucky you won't bin it.

It is entirely possible that a chain develops tight and loose spots so you need to check at a number of points, once it has done this it is shagged and its time for a new one.
 

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When you pull the caps off the tubes and you get a good whiff of that old fork oil, you'll be happy you changed it.

The damper rod forks are super easy to work on, unless you're replacing the damper rod itself. I've heard the cartridge are easier, but I have no experience working on them myself.

Standard cartridge forks yes, USDs....

USDs are one of my two reasons that I need a bike shop,
1) is to sell me bikes.
2) is to do my fork work, I friggin HATE doing USD forks, I've known how since I was a pre-teen, I just happen to be in a place where I can pay someone else to deal with that bullshit.
 

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Standard cartridge forks yes, USDs....

USDs are one of my two reasons that I need a bike shop,
1) is to sell me bikes.
2) is to do my fork work, I friggin HATE doing USD forks, I've known how since I was a pre-teen, I just happen to be in a place where I can pay someone else to deal with that bullshit.
My hatred of working on USD forks is only slightly beaten out by my hatred of letting anyone else touch my bike.

OP, conventional forks are simple. Call RaceTech and talk to them. I'll guarantee you they have some springs you can use. Prolly be $150 or so.
 

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My hatred of working on USD forks is only slightly beaten out by my hatred of letting anyone else touch my bike.
:loller

I'm the otherway around, while I'm generally loath to let people screw with my bike....

...yeah, still not doing that shit.
 

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with no one on the bike, the slack is a bit over one inch, so it should be snug when i'm sitting on it.
No, it shouldn't.
In the meantime, I'm rethinking that I should drop teh front end. It's not a supersport and its designed to be more 'soft' but i'm thinking one inch down from the forks should be enough to change teh geometry of the bike but not creating any riding risks.
No, you shouldn't.

Your chain should NEVER be "snug". It should have a little bit of slack throughout the swingarm's entire range of motion. If the chain is snug that means it's binding up the rear suspension, hindering it from doing its job. My race bike has a TON of slack. This does not have any effect on how the chassis handles, other than the fact that it lets my swingarm move freely through the suspension range.

As for dropping the front end, an inch is an ENORMOUS change in geometry. Dropping the front end makes the bike LESS STABLE side-to-side. Although that makes it more maneuverable, it removes stability. Too much and you're doing more harm than good.
EVERY bike will "raise up" the front under acceleration, because that's what physics tell it to do. As a bike accelerates, weight transitions to the rear. As you decelerate, it transitions towards the front. That's physics. Stiffer suspension will help reduce that, but weight transitions do have benefits to handling so you do want some transfer of weight.

If you don't want it to "po-go" stick as much, then you need to look at stiffer springs, thicker fork oil and/or different compression or rebound settings.
 

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I keep my chains on the loose side, I'm just careful with alignment. They last a lot longer than keeping them tight.

But to your fluffy suspension issue, aren't those forks just damper rods? If they are, get some fork oil, some thick-walled PVC pipe and some metal pipe. The pipes should be similar in size to your springs. Change your fork oil. Cut a longer spacer out of PVC pipe. See if it makes a positive effect. Keep going until you're happy or can't cap the forks. When you find a good PVC length, re-cut your spacer with good metal pipe.

The idea is it flattens out the spring rate on the progressive rate springs and makes them more linear. Truth be told, real flat-rate springs are a better choice, but if you're hesitant to buy them for whatever reason, playing with spacers is sort of, "let's see if it fixes the problem" process.

If you ever use the brakes for anything other than slow and easy stops, raising the forks an inch in the triples will mean that you'll end up hitting the triple with the top of the fork legs.
So youwant him to crank out the preload?

That doesn't do anything to change spring rate, it just makes the forks sit higher in the suspension range... maybe too high.
 

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So youwant him to crank out the preload?

That doesn't do anything to change spring rate, it just makes the forks sit higher in the suspension range... maybe too high.
Depends.

Assuming that they are progressive springs (which would be pretty normal really) what it does is get the spring out of the "soft" end of the travel so you are using the higher spring rates at the "bottom" of the travel. I tried something like that with my Speed Triple when I was trying to un-fuck that thing's suspension.

I ended up scrapping that idea and just getting straight rate springs.

I could see how a damper rod fork with a "soft" end on the springs would make if pump like crazy.

(lol it would feel like a softail)
 
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