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Discussion Starter #1
Hi Guys, I have just go my SP 1 on the road. this bike was a repairable write off to start with. Up until now my ride has been an 05 fireblade, nice and firm on the road. The issue I have, is the bike steers very quickly, too quick, a slight lean and the handlebars alomost fold into the tank, you really have to fight to hold it up in corners. The forks had been lowered in the clamps 8mm which I reset to original, made no difference, or very litttle. It has new tyres (power pilots) and the forks are being serviced today. I have heard of a 5 mm spacer under the rear shock. If this has been done, how much effect would it have on the steering? any help would be great. cheers damagemax1
 

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Definitely get the bike back to standard setup and then at least you know where to go from there. Make sure the forks are back to factory placement and if you are an aggresive rider then maybe you should consider fitting a steering damper to help control the steering. My bike definitely does not steer so quick that it feels like the bars want to slam into the tank!! that sounds quite scary actually... I hope you get it sorted.
 

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You mentioned a spacer in the shock. That, and the rear tire size will affect how easily it tips into a turn. According to Dan Kyle, and many many others that have used it, a rear shock link also increases ease of turning. I've heard of using a shim, or spacer like you mentioned, in place of a proper link. That's different and could have a negative effect. I don't know, I've never tried it.
What size is the rear tire? Stock is 190/50-17. That tire will tip in slower than 190/55 will. But many here, including myself run the 190/55 for that very reason. Some run a 180/55, but I think you need a 5-1/2" rim for proper mounting. Our stock rims are 6"
It sounds to me like you just got all the wrong geometry going on.
I don't know your ability or knowledge, but when you say the forks are getting serviced, what exactly is being done? Just a fork oil change? They should check the service limits of the springs too, assuming they're OEM. Which are meant for a rider in in the 160-180 lb range. So obviously, when you get the bike and forks back, set your riders sag front and back, and work with your compression and rebound settings.

One last thing. It was a total? Was it wrecked, if so then there's a lot to check for straightness. fork tubes, lower and upper bridges (triple crowns), steering stem, clip-ons, frame, brake rotors, probably more I'm just not thinking of.
 

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Does this problem occur both left and right turns or predominantly one side more than the other?

If it was more one side than the other I would tend to lean to the notion that the bike may not be straight. A bit more info maybe...
 

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My bike felt loose like you described and I ended up going over the suspension and had it properly setup for me. The biggest help in the front was +8mm, 1 line of preload, 5 clicks of rebound, and 16 of compression. IIRC I started with the settings recommended by Performance Bike magazine. For my style and common terrain this tightened up the bike and only allowed turn in with decisive input. It also now tracks like its on rails.

Set it to stock, see how it feels and go from there. The stock settings where just not right for me with the Ohlins rear and +4 so I tried numerous suggested start points until I felt comfortable.

Edited to add: like mentioned check the physicals on the bike. Straightness, proper torque on the steering head....you can't tune out jacked up construction or parts;)
 

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Discussion Starter #6
thanks for the responce, the forks are having the springs checked, new fork seals and oil. He is going to check the valving as well for starter. Back tyre is a 190/55. I have ask the suspension dude to set everything back to factory settings for a good starting point. I'm a heavy vehicle mechanic by trade working on mining equipment but when it comes to my bikes other pulling down for servicing and putting this one back together, I leave everything to the bike shops. I think your on the money with geometry thing, so starting from stock will help. i hope its not frame related. Cheers
 

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Also check if the lower rocker arm on the rear suspension is OEM or if a Kyle Racing link has been fitted.
While beneficial on an SP1 (2000-2001) it isn't necessary on the SP2 (2002-2006) as it had revised linkage.
The Kyle link on an SP2 raises the rear ride height by several millimeters that can quicken steering response.

And if an aftermarket shock is fitted (Ohlins, Penske, etc.), check if the ride height adjustment near the lower attachment is extended. The adjuster has a maximum travel of around 10mm, which can also cause quicker steering response.

The OEM setting on the front forks is with the first line down from the top (approx. 5mm), level with the upper triple clamp.

With suspension, the best way is to return it to baseline settings, then make minor changes and write down the settings and note the effects for future reference.
 

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While your suspension guy is at it, make sure the fork tubes are set to OEM height in the triple tree clamps...and evenly set.:cool:
 

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Discussion Starter #9
Again, thats for your help so far! here is where i'm at today. the forks have had new, bushes, seals, oil. the forks are now set on the first setting, 5mm from top. He did find a very slight bend in the r/h fork tube, not enough to be massively concerned as I 'm not Casey Stoner, but still he said it is there! A new 190/50 will be fitted this afternoon and when I get it home I will remove the 5mm spacer from the rear shock. the bloke at the suspension joint took it for a quick test ride and believes it to handle 100% better than before. this is good so far, the true test will be this weekend. I will keep you all posted.
 

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Ok, I suspected the possibility of a bent fork tube. That's why I asked you if the bike was wrecked. I don't recall that you answered that question. You need to find out if it's within the service limits. Not just 'slightly bent'. Doesn't matter if your Rossi or Ricky Racer, the tube needs to be within those service limits.
 

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Personally, I would have installed a 190/55-17 rear tire.
I found the steering response was much,much better than the 190/50-17.
 

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Discussion Starter #13
understerring SP1

Ok guys, here is the latest. I picked the bike up and suspension guy informed me that the r/h fork tube was not bent but was slightly ovaled at the top from being clamped in a vice too hard possibly. this has caused more wear than normal in the upper area of the tube. He replaced the bushes and the this has reduced any excessive movement, in saying this, I wold imagine the fork life will be reduced somewhat. Any way I can't afford another fork tube just yet. so i took the bike for a ride last night and I'm blown way by the difference, i don't know if it will require further adjustment just yet as I have been up the mountains yet and I will never outride the bikes capabilities. thank you all for your help and advise, take care and stay upright. Cheers PS I will post some photos this wek end.
 

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Check the shortest distance of the front tire from the lower cowling (What is the measurement) and show us some good side on pictures. Just be sure it hasn't hit something head on and bent the frame.
If it has I'd assume it's not too bad and so it would be possible to straighten - but the bike flopping into corners indicates not enough rake of the forks. Can also be caused by too high a rear and low front. But it's all relative.... A good side on pic with the bike on a paddock stand can sometimes show if something's visibly wrong...
 
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