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Discussion Starter #1
A buddy of mine recommended lowering my forks slightly to try and improve cornering with less effort. I did lower them approx 7.5 mm (.75 protruding from the triple clamp ), and the turning definately imporved. The problem is that at a certain point in the lean it seems as though the back just wants to slip out on me. I know the tires aren't slipping but it just feels that way. i've played around with the bike a little and it consistantly seems to be doing this.

I didn't touch the suspension after the setup so could it be a suspension tweaking issue due to the front end lowering??


Anyone had this also?? and what did they do to fix this.
 

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I've always read in the mags about fork lowering for cornernig. But i think they only lower them like 3 mms. try raising them back up a little bit. Fireblades are supposed to be the quickest steering bikes in stock form anyway.
 

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Yeah, the 954 is about as sharp a turning motorcycle as you can get your hands on, almost too willing to fall in and overly communicative for some.

Do you have a damper? I'm just curious. I used to run a SCOTTS and actually prefer the bike damperless now, but holy cow, I can't imagine my bike turning any more rapidly than it does!

Good luck sorting your problem. I think this change in the geometry of the machine has likely opened a whole nuther can 'o worms for you.
 

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Discussion Starter #4
well i just happened to run into another guy with an erion today, and while googling over his bike i noticed that his forks were lowered more than mine ( 10mm + ). We talked about the turning and he says that i'm just not used to it dropping so fast. I guess i have to get used to it. I'll take a look at some other 929 setups to see if they are lowered.

When i got it from the shop, the forks were up to the little line on them ( ring). so only about 2-3 mm's were showing. I'm wondering if other peoples forks were adjusted differently before they got their bikes.
 

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It will take a while to get used to the handling. I jacked up the rear of the 929 around 7mm or so. That combined with the Michelin S2/M2 tires really changed the handling of the bike. Took me a little while to get used to it. Now that I am used to it I want to adjust it even more.

FYI, I have already dropped the RC front end by 10mm and am thinking about going down another 5mm. Not sure yet though. I might just shim the rear a little bit and see if that helps it out enough. After getting the 929 set up better for turning I finally got tired of having to drag the RC down in a corner and am on my way to making it a better turning machine. The RC is planted as hell in the turns but it took way too much effort to get it leaned over.
 

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I don't know who should answer this first, LTL or I.

Lowering the triples onto the forks on the 929/954 is a bad idea, and once you exceed 120 mph in a straight line you will realize this yourself if you don't get blown off while traversing a small bump.

This has been discussed in so much detail on this forum and Motorush that I refuse to go into the physics again. But believe me, if you need to make the bike take less effort to turn it in, you need to start working out or rethink your riding style. The bike has too little trail already, and lowering the front end does not put more weight on the front wheel as everyone thinks (well, it actually does, but even at 10 mm, it is less than a pound). It does screw up the slight bit of straight line high speed stability the bike does have, beyond that it kills any chance of hard cornering on the brakes as all of the hard parts and bodywork will be grinding away.

This is a Darwin modification and should only be performed by posers. Most fast guys actually raise the triples to add trail and get some additional ground clearance. Sliding your butt another 2' forward while turning will make the bike turn WAY easier than lowering the front end ever will regardless of amount of drop.
 

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Yep---Ab is dead nuts on--NOT to mention---you may get some surprises in lost ground clearnce---whenst you are cornering hard and you deck out your stator cover and fall on your bum
 

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Agreed bike is already starving for trail. Do not lower the front end. Cowboy and myself are both starving for clearance as it is......And we both still manage to have front end shakes even with the suspension dialed......
 

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yep,

lost ground clearance, instable and the tucking feeling at full lean, put them back up flush and raise the rear.
 

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Decent article in this months Sport Rider by Andy Trevitt that relates some of Tony Foale's observations regarding the relationship between lack of trail and stability. Tony's books are true seat of the pants empirical data gained from playing 'what if' in real time to test some of the physics. A bit dated, but they usually don't change physical law every other week . . .

pp 96 in the October issue.
 

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Discussion Starter #11
thanks for the suggestions.

So if i put the forks back to the original position and raise the rear a little would that serve the same purpose yet eliminate the instability??
 

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MACI4LIFE : thanks for the suggestions.

So if i put the forks back to the original position and raise the rear a little would that serve the same purpose yet eliminate the instability??
That is the way to go. But raising the rear will also add some instability.

It's basic physics as Ab pointed out. Anytime you make something easier to turn, it becomes less stable. Witness modern fighter jets, so unstable they can't be flown by a human.

Get the forks flush, and raise the rear if you want, just be ready for it to shake more.
 

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MACI4LIFE : thanks for the suggestions.

So if i put the forks back to the original position and raise the rear a little would that serve the same purpose yet eliminate the instability??
If you really want the bike to turn in faster, try some tires with a more triangulated profile, or as I mentioned before, sit further forward in the seat.  Raising the rear has many of the same negatives as lowering the front (it's usually more expensive as well), although it does have a positive effect on ground clearance.  Off corner drive may change (in a bad way) if you go too far and the bike will begin to oversteer (the same phenomona you are having now when it feels like it's going to come around).  

If you aren't pushing the front tire now, then it's not too hard to turn.
 

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Discussion Starter #14
I'm running the bt-010's right now. I will get the 012's next year as these ones are getting worn ( most likely giving me the leaning problems. back is starting to square off ( which is probably why it wants to tuck at that certain lean point). I didn't feel it for the original settings so i'd have to assume that lowering the front made the feedback a lot more sensitive.

I guess i'll put the settings back to original, and just ride out the season until the new tires and then buy a spacer for the rear shock and start tinkering from there.

Thanks for everyones help. I've been reading pages of info from other forums and they all point to what you guys say.

lower the front = faster turn in, but increased instability.
raise the rear = faster turn in, more ground clearance, and less instability than lowering the front ( lesser of 2 evils ( can't get away from the geometry of the bike)).
 

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the bike flicks from side to side quick enough as is. try sitting more foward like everyone else suggests and make a note of you body position. also try weighting the pegs a little. (try lifting off the seat just a bit as you countersteer) then tell me if you still think the bike steers slow.
 

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Just get a set of these, it's that easy

 

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Discussion Starter #17
ok ok it's going back to normal. Too much instability while riding. Definately not confidence inspiring.

time to take the 101 on leaning again
 

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Ok, I am not trying to argue with people here who have obviously spent more time around chassis geometry than me. However, I have raised the forks in the clamps (effectively lowering the front end) of the 929 a small bit. I also ran up the rear end a good bit. While it did take a little bit of time to get used to how much easier it turned in, the bike is not unstable. Believe me, the first test I did was to go out to the track and run the thing up to 150MPH to see if I got any wobbles. Also, different tires have different diameters. If you do get your bike set up a certain way that you like then if you switch tires you might have to adjust the front and rear height up or down to regain the geometry you like.

It just sounds like you guys are giving the impression that messing with the geometry in just about any way is a bad thing and that most people do not do it because of the negative effects. In fact, most people I know (including racers) do change the geometry on their bikes at both the front and the rear. It isn't something you want to go and make big changes on, but I guess I don't understand why you guys are making it out to be such a bad thing.

BTW, if I remember correctly LTL, wasn't your bike so unstable at Grattan last year that it wobbled the whole way down the straight? What all did you have done to your bike regarding geometry to get it that way? I assume you were willing to live with it to pick up an advantage elsewhere.

Not picking a fight or anything. I am still low in the learning curve in geometry and am willing to listen. But I can say that the small change I made in my front end made me happy with the handling. The only complaint I have right now is I seem to run wide in turns and it might be related to the front end change (not sure though, it could be other things).
 

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Well after the dogbone, Ohlins forks, some shimming on the rear Ohlins ---my bike is definitely more unstable than stock---however unlike LTLs---most of the instability can be managed--as it usually starts hard on the gas exiting corners--some body positioning usually takes care of it--however, I would argue that my bike is right on the edge and many people wouldnt want to ride it that way.

BUT I have seen too many people crash cuz they are decking out the stator cover to even think about lowering the front
 

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LFG: My 929 was way modified from stock, and it handled just the way I wanted it to. I added more than 1.25' total rear ride height (not shock length), but added only .5' front ride height which is still reasonably radical. I didn't do this to make it steer faster/easier/quicker or anything of the sort. I did it to gain ground clearance and with the right selection of tires and suspension setup was able to minimize high speed instability while getting the drive off of corners that I wanted.

If your bike is running wide off of turns and you have raised the rear and dropped the front, it's probably time to look for another brand of tire, as these mods usually have the opposite effect (oversteer).

The 2000 & later Blades are really an exception to the rule regarding lowering the front end and this is due to several basic design considerations of this chassis. The largest factor is the location of the swingarm pivot point and it's relationship to the overall 'lever' point in the chassis. Honda came up with this design to gain some swingarm length without vertically stacking the trans (ala R1) and once they added the swingarm length (nearly 1' over the pre 2K Blades primarily to make it more stable at speed), they decreased the trail to provide quick turn-in. This cocktail of numbers has produced a bike that is very nervous at speed over any surface irregularities and particularly when coming out of the draft at high speed.

Further reducing the trail by lowering the front end makes this problem even worse, especially when combined with the 929/954 canard style fairing which actually produces positive lift at speed.
 
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