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Discussion Starter #1
Is a increase in ride height equal to an increase in seat height? For example if the seat height was 30 inches would increasing the ride height by 5 mm increase the seat height by the same amount?

Reason I ask is because my MV feels like a 999 or an MV with a flat tire since the seat level is almost parallel to the ground. When I bought the MV, it was waaay to tall so we lowered it. After 900 miles, I think the suspension has broken in and rear end has sagged a bit.

So, my MV is at Pro Italia getting it's first service and I've asked them to raise the ride height between 3 to 5 mm. I realize it's a compromise between better handling and not spending $700 because I dropped the bike but I'm just trying to get that good middle ground. I don't think a 5mm increase in seat height will be a problem.

Just FYI, I'm 5'5 with a 30 inseam. I have Spidi boots that give me an extra inch with makes the current height doable. On the otherside, I'm also 215 pounds (yeah, I working on it) so I think that's help sagged the suspension. My rear suspension settings are on stock and front suspension is a few click softer than stock.
 

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Considering your height wouldn't a bit of suspension sag be ok?

Now 3mm is just a thick pair of underdacks - not much! HeHeHe!
 

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Alan, yes ride height and the seat height are related. The steering is due to the geometry change they created by lowering the bike. What you need to do is decrease the rake angle to get the bike to steer properly again. You can have them raise the rear and lower the front to get the bike back in the ballpark without raising the seat height too much.
 

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Discussion Starter #4
Sag is good if I didn't ride canyons to work everyday. But it makes my MV feel like the front turns and then the back follows -instead of one perfectly integrated piece.

Like I said, it's a compromise. I doubt I could go more than 5mm on the rear and I think the front is as low as it can go.
 

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Set the sag to some sane number, I'm not sure what it should be for that bike exactly... Probably something like 30mm. You'll probably want 35mm for the front.

Then set ride height from there with the ride height adjuster, not sag. The sag might change a bit due to ride height, check it again after doing ride height.

You might also be able to achieve a similar goal by lowering the front. That's kind of a no-no on the 750 because of tire clearance, but I think the 1000 isn't so bad? Not sure...

Back to the original question, yeah, increasing ride height 5mm is related to the seat height, but it's not 1:1. The 5mm increase should be measured vertically from the rear axle to somewhere on the tail section. The seat will go up a little less.
 

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If you only change rear ride height (or front), you alter geometry. If the goal is to change steering response, then a change in geometry is appropriate. If you are concerned about seat height, then you must alter both front and rear ride height to approximate the same geometry.

Of course those changes will cause a change in CG and swing arm angle which have other consequences. It's always intertwined and not so simple unless you are only pottering around.
 

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Discussion Starter #7
Thanks for your responses. Since it's not a 1:1 change, I think a 5 mm increase will be okay.

I left the setup to Pro Italia when I got the bike. We spent most of Saturday working on it and it handled perfectly for about a week. At first I thought I was loosing air (even started a thread about that) but I believe it was the suspension just getting broken in.

It's kind of funny that when I lived in Phoenix, I'd ride the canyons maybe two - three times a month and the set up won't have really bothed me. Now that I drive through canyons daily, I'm more aware "attitude" of the bike. :)
 

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Adjusting in 5mm increments is appropriate. At least that's the way I always approach it so I don't go overboard.
 

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Another option for the geometry is to look at tires. If you are limited by the front, i.e you can't lower it anymore, you can consider changing the tires. Different model or make tires have different diameters even though the tire sizes are the same. A little detective work can yield a front tire with a smaller diameter or a rear tire with a larger diameter. This will net the same effect as raising the rear or lowering the front.

Another thing to consider is the compression damping. If the front is a little soft you can get a little delay between the steering input and actual turn-in. Adding a click or two of compression will get rid of the soft feel if that is the culprit. Of course you should check tire pressures also. My inclination though is to believe that the geometry is out of wack because of the suspension change.
 

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Discussion Starter #10
Ack. My MV hasn't been at Pro Italia for more than 24 hours and already I'm getting separation anxiety. How many more hours till Saturday! :)
 

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Alan, here's a little trick for you...

Run HEAVIER springs front and rear but reduce the amount of preload. This will give you lower ride height and the heavier springs will keep the suspension firm enough even with less preload. Though it's counterintuitive, heavier springs with less preload generally give a plusher ride and that is especially true for heavier than average riders.
 

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Discussion Starter #12
Well, I got a call from Pro Italia and they're working on my bike as I type this. Service manager called and said the mechanic who's working on my bike and also did the original setup, realized that he did NOT lower the front end to match low rear end! No wonder! :banghead:

And for us short riders, someone asked for a picture of me (5'5", 30 inseam and 215lbs) on my bike. I'll take and post on Sunday which will show the lower setting.
 

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QUOTE=Allan Gibbs]Well, I got a call from Pro Italia and they're working on my bike as I type this. Service manager called and said the mechanic who's working on my bike and also did the original setup, realized that he did NOT lower the front end to match low rear end! No wonder! :banghead:

And for us short riders, someone asked for a picture of me (5'5", 30 inseam and 215lbs) on my bike. I'll take and post on Sunday which will show the lower setting.[/QUOTE]

Lowering the front makes more diffrenece than raising the rear, My R runs wide and stands up under brakes (or would do without some more rider effort) when my forks come back I will raise them through the yokes about 8mm like I did on my S, that was one sweet handling bike :naughty:
 

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Discussion Starter #14
Yes, it really does. They lowered the front by 1/2 an inch! First thing I notice was the my bike looked physically smaller. When I got on, it felt exactly like my old 750 did and the center of gravity was much lower! :) And handled like one piece - as oppose to the front and the back which pivots around the front.
 

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mikef4uk said:
QUOTE=Allan Gibbs]Lowering the front makes more diffrenece than raising the rear, My R runs wide and stands up under brakes (or would do without some more rider effort) when my forks come back I will raise them through the yokes about 8mm like I did on my S, that was one sweet handling bike :naughty:
Well, maybe. It's not so simple. Lowering the front makes a different change than raising the rear. Although you might think it's intuitive to see that lowering the front X amount or raising the rear X amount equals the same thing (geometrically), this ignores the other factors involved.

Changing rear ride height also changes chain angle. Any change in chain angle will result in a change to the force applied around the swingarm pivot point. This change can cause the rear of the bike to raise or fall under acceleration (i.e. turn exit). Of course this has a dramatic effect on handling if the bike has sufficient power.

It's not so simple.
 

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:wtf: :jsm: :wtf:


If your playing with it. You need to be there with your full riding gear. The bike needs to be weight front to rear. Notes before and after need to be taken. Raisng rear end can change the fork angle, On these bikes little goes far. Playing with spring rates to lower a bike is also a bad idea.

The sag rate is the proper tension for the spring to work with the dampening dailed into that fork/shock. Going to a shorter stiffer spring can, make use of the bump stops, allow for 1/3 less travel, take the dampening and toss it out with your kidneys.

Set the bike up at a baseline.
Check wheel alignment and tire pressure.
Set sag rate rider wearing all riding gear.
roll bike onto scales on measured flat floor. Check for unloaded weight load.
Add rider, Check for weight over front to rear.
Adjust ride height on scales (rider on board)to keep weight limits set by riders riding style.
Check ground clearance,
Steering head angle.
Swing arm angle
Chain tension (chain pull)

Now during the sag set up, you should have a range that is found, You will then know if you need to go up or down in spring rates, When adding new springs, Fresh oil, and revalving should be done. You go up in springs, You need to match the valving to those springs.

I can knock a few seconds of most track day riders just resetting sag and adjusting front to rear weight bias, tire rise pressure.

Take notes on everything you do. Even better if your doing a track day. write notes everytime you come off the track. Helps take the guessing out if you go the wrong way.
 
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