Drop It Like Its Hot!!

[sokanxx]

I am planning on lowering my front end next week. I want to quicken up the handeling, as much as I just think the bird would look better with the nose down. im asking how much can i safely lower the the front before handling becomes too quick, or make it unridable? Oh and I will be sliding the forks up threw the triple tree, rather than just strapping it down. I put about 7,000 miles a year on the bike so i need it to still be ridable, but I deffinatly want the most drop i can without sacraficing too much drivability. I know this is a personal opinion question. oh and i will be keeping the back end and factory height. - Thanks !

[Squareman357]

Did you already do the 6mm shim on the rear? I'm told that quickens the handling considerably.

[Guest rockmeupto125]

I wouldn't drop it more than half an inch. More than that is waaaaay touchy. And don't take your hands off the bars ever.

[sokanxx]

No I havnt shimmed the rear. I would like to leave the rear as is (stock height). I'm thinking about 15mm drop in front. but just wanted to verify that it wont be too much of a drop. I am wanting to do this for 60% looks, 40% handeling (squidly I know!), so i'd rather leave the rear height stock.

Any ideas on if 15mm is the max I should reasonably drop the front with a stock rear, or can I go down more in front because the rear is stock? Please take into consideration that I dont want the fender slamminginto the bottom of the tripletree or anything dumb like that happening.

Again thanks for your replies this forum is great!

[sokanxx]

my fast math saysthat 15mm is about the same as a half inch. I guess 15mm is .59 inches to be exact. thank you google search!

[Squareman357]

Some bike wiz can correct me if I'm wrong, but wouldn't the 6mm rear shim and a 8 or 9 mm drop in the front still give you the same effect without having to drop the front so far? What are you really trying to do?

[Dion]

I would shime the rear first. This will quicken your steering and give you time to get use to the change.

I would not go 15mm right off the bat up front. this would be a radical change and will lower your clearance remember.

Mine is shimed 6mm rear and forks are dropped 1cm. But I also upgraded the springs before dropping the front.

It does make the kids on the 600's wonder how such a big bike can turn like that but,.... I can also feel that these changes are pushing up to the edge of stability for me on the bike.

"Remember Ellie small moves"

[sokanxx]

I totally dig the look of the DragRacer Blackbirds, with the fronts slammed so far down, but i know that this isn't reasonable for everyday riding. but would like to get it as low as possible without sacraficing everday practicality. I guess thats my main goal here.

[CBRBob]

I did 5mm up front. It was good. Then I made it 10 and the bike seemed somewhat nervous, needing constant attention. I went back to 7mm and it was fine. (Correct springs in the forks). I added a Penske shock a year later that was slightly longer that raised the rear about 10mm and it quickend the steering a tad but did NOT make it nervous feeling.

For looks, do what you may, for real benefit, raise the rear and stay away from fork straps on the street.

[Guest rockmeupto125]

Mine is dropped 8.5 mm.....pretty close to Dion's 10mm. I judged it to be just too nervous when I dropped it any lower. I also have much higher rate springs than stock...which means that the forks don't compress as much as yours might...minimzing the total "drop."

Anson, the difference between dropping the front and raising the rear may seem inconsequential at first, but they actually accomplish different things.

Raising the rear keeps the chassis geometry intact, but more closely maintains the steering head angle while altering the rake and the trail.

Dropping the front shortens the radius arm of the front forks, and WILL significantly alter the steering head angle. Generally, anything more than a half degree of change from a stable setting is going to produce significant and potentially costly results. Dropping the front 10mm yields about 0.385 degrees of steering angle alteration on a 1485mm wheelbase, resulting in quicker and more sensitive steering. 15mm would make 0.589 degrees. Way quicker steering and sensitive to random thoughts and nearby boom boxes. Not recommended.

[brianmacza]

This is likely to affect ground clearance as well, isn't it?

great for getting a knee down in campus

[Dion]

This is likely to affect ground clearance as well, isn't it?[/qoute]

Yes

And without the spring upgrade is more likely to compress even more. Look at Joe's lower fairing and I've banged the header a couple times which is scary when you feel the wheels un-weighting.

great for getting a knee down in campus

Honestly, I don't think the Bird is made for getting a knee down. The shape and size of the bike means you need to be really off the bike and right on the ragged edge. I've done it once but think it was mainly because the shape of the road came up to meet my knee.

[blackhawkxx]

For looks, do what you may, for real benefit, raise the rear and stay away from fork straps on the street.

Put a strap on it but leave it loose, when you get to your biker hangout, pull the strap tight. Loosen before you leave. Oh, don't forget to shorten your kickstand.

[Squareman357]

Mine is dropped 8.5 mm.....pretty close to Dion's 10mm. I judged it to be just too nervous when I dropped it any lower. I also have much higher rate springs than stock...which means that the forks don't compress as much as yours might...minimzing the total "drop."

Anson, the difference between dropping the front and raising the rear may seem inconsequential at first, but they actually accomplish different things.

Raising the rear keeps the chassis geometry intact, but more closely maintains the steering head angle while altering the rake and the trail.

Dropping the front shortens the radius arm of the front forks, and WILL significantly alter the steering head angle. Generally, anything more than a half degree of change from a stable setting is going to produce significant and potentially costly results. Dropping the front 10mm yields about 0.385 degrees of steering angle alteration on a 1485mm wheelbase, resulting in quicker and more sensitive steering. 15mm would make 0.589 degrees. Way quicker steering and sensitive to random thoughts and nearby boom boxes. Not recommended.

Thanks Joe. So why would you want the steering that quick? The Bird is generally a very stable platform, not prone to tank slappers and other front end shenanigans. Wouldn't that drastic of a change affect that in a very negative way? I can understand drag racers slamming it to help keep the front end down for high speed straight line acceleration, but they don't care about handling. Why would you want to do that to a street bike?

[blackhawkxx]

Dropping the front shortens the radius arm of the front forks, and WILL significantly alter the steering head angle. Generally, anything more than a half degree of change from a stable setting is going to produce significant and potentially costly results.

Joe, would this also apply if the rear was dropped the same amount?

[Guest rockmeupto125]

Reading back, I realize (hey, it was late at night) that I left a little bit out. I mentioned the effect of relocating your front suspension pivot points (dropping or raising the front end) as changing the head angle, but neglected to mention that the reason that is important is that it drastically changes the trail. Same effect, just didn't follow through with the equation.

I also didn't clarify that raising the rear leaves the FRONT chassis points intact, but obviously does change the static settings in the rear, specifically the swing arm angle. We're blessed with a fair amount of travel in the rear, and most of us weigh enough so that the rear suspension compresses enough not to profoundly change the handling of the rear. Shock linkage rates can get a little different when you play with the suspension like that, so small changes are in order rather than big jumps. And that's not even considering the changes in wheelbase.

*Blackhawk----No. Dropping both the front and the rear will leave the steering head angle and thus the trail untouched. The problems are that you'll drop ground clearance, and change your rear shock rate. And the bike will fall over if you try to put it on the kickstand.

*Squareman----The way mine is set up, its not "THAT quick." Its quicker, but not unstable. And the reason? Well....I saw a picture of your bike earlier today in another thread. Looks great, but it sure doesn't look stock. Why did you make those changes and modifications? "Because you wanted to" would be a realistic answer, but looking deeper, that means "to make the bike fit you and your needs."

The XX, like any other production bike, is an average of what the manufacturer perceived as its probable uses. Our bikes were designed to do a lot of things. They CAN do things they weren't designed for....we are all evidence of that. But we change the bikes to fit our bodies and the way we ride. We add hard or soft bags to carry supplies because we spend days on the bike. We raise and lower footpegs, add new ones, use higher windscreens, lower wider harder seats, higher bars, different brake pads, etc, etc. its just part of tuning the motorcycle for what you use it for.

After a day in places like SEXXT, or on the Dragon, I appreciate the decrease in steering effort made by dropping the front 8.5mm. The little bit less tired I am at the end of the day might make a difference in dropping the bike or not....this IS an extreme sport. I could just suck it up and deal with it. Same for touring...instead of mounting a higher screen, one could just suck it up and deal with the constant buffeting/wind blast....that makes you tired, and at higher risk for an error. So tuning your bike, whether its steering angle, screen height, or volume of your MP3 player makes good sense. Sometimes its even fun, too.

That's why.

[sokanxx]

Thanks for all your suggestions. After reading them over I think I will just leave the suspension alone. I would rather be safe then look cool.

[EVLXX]

Here... let me fuck it all up....

I've had my front end dropped for over the last year...

Turn is very sensitive, but too me ... not twichy. I like it.

I have also made a few high speed sweepers and ultra high speed passes... without any head shake. ( I think the tires you put on have more to do with this problem )

Set my sag...

Life is great.

20mm of drop up front... zero change on the rear.

[Skull]

I put a 1" lowering link on the back and slipped the fork tubes about 1". I'm getting ready to slip them another 1/4" or so, fwiw.

[Pete in PA]

I would think somewhere at 3/4 in. to 1 and 1/4 in. you would hit the fender into the fairing with hard braking.

That's NOT cool.

[Skull]

I would think somewhere at 3/4 in. to 1 and 1/4 in. you would hit the fender into the fairing with hard braking.

That's NOT cool.

It seems to be getting to that level, but not there. Quite.

I am investigating some bump-stops that would prevent that in case I do cross the line.

[EVLXX]

20mm is about 3/4 of an inch.

I have not hit the fairing on the fender... but I have touch the lower plastic down in a mid corner bump situation...

I chaulk the scratching up to needing to loose some weight and packing lighter, though.

I love the way she turns in now.

[Mitch_1100xx]

my front is down 1.5 inches, and i havnt hit bottom yet, though i havnt been under really strong braking. i plan to stiffen the front. though i am consiterably light at 175 lbs.

[Elefant]

I did 5mm up front. It was good. Then I made it 10 and the bike seemed somewhat nervous, needing constant attention. I went back to 7mm and it was fine. (Correct springs in the forks). I added a Penske shock a year later that was slightly longer that raised the rear about 10mm and it quickend the steering a tad but did NOT make it nervous feeling.

Ditto. There is no "this much and you'll be fine". How much do you weight? Depending on that along with the spring rate you have, you bike rides at a certain height. I'm 170. If I ride your bike and you weight 130 I'm already riding lower than you. If your 220 lb cousin borrows it, it'll be pretty dam low. I really think it's a trial and error deal. When I get a new (to me) bike I always experiment and try to find the spot that suits my riding style on the bike.

I have a bike I use mostly for track. Spring rates and preload are set towards the stiffer end. That causes the bike to ride with the suspension extended more than a regular street bike so I have to make up for it by lowering the triples so that the geometry is still confident inspiring. If I lower it too much too twitchy and nervous. If not enough, the bike will tend to go straight no matter how much I try to dive into the turn. So the forks stick out of the yokes substantially more than a regular street bike. But the suspension is still functioning where it's suposed to be and and chasis has a somewhat good geometry set up.

Try different set ups and see what suits you.

Did I make sense?