Tyre Pressure and Suspension adjustment

Sailariel · January 5th, 2009, 03:19 PM

Alex, I read your very informative narrative on the Literbike crash and how a combination of confounding variables could have been the culprit. My 08 Ninjette is completely stock (and will stay that way) I can not find anything in the Owner`s Manual or Shop Manual that tells me what tyre pressure I should be running. I have the OEM Dunlops and have been running 32Psi in front and 36Psi in the back. I weigh 195. The bike seems to handle well and I basically ride secondary roads at 55 to 65mph. Also, where does Kawasaki set the rear shock at the factory? The book is quite vague as to where it should be set. When I take trips, I carry about 30lbs of luggage in a tank, tail, and saddle bags. That gives me a laden weight of approximately 225lbs. What would you recommend as the proper tyre pressure? Also which notch should I set my shock absorber on? Thank you in advance. Alex II

kkim · January 5th, 2009, 03:42 PM

Recommended pressures are on a label on your swingarm, right below your chain. 28f/32r.

I ran 28/28 f/r with the stock tires.

As far as rear preload, with the luggage weight, I would bump it up one notch from your "regular" shock notch setting.

To determine what your "regular" shock setting should be (I don't know your weight), I kept bumping my shock up one notch at a time until I felt it was too stiff for my type of riding and backed it down one notch.

The shock comes set at the lowest of the 5 settings from the factory. All tools needed to adjust is in your tool kit that came with the bike.

Alex · January 5th, 2009, 03:56 PM

Hi Alex -

With tire pressure and suspension adjustment, they are two areas where there is never going to be a single correct answer, with all other answers being incorrect. By their very nature, the choices must come in ranges, and people's preferences will play a role in what they feel works best for them.

With that caveat, here's what I think.

Stock tire pressure, recommended by Kawi, measured cold, is 28 psi front and 32 psi rear. Anywhere within +/- 4 of those numbers won't result in a terribly unsafe motorcycle, but at the extremes the rider would likely notice a mushiness (on the low end) or a harshness (on the high end). Within reasonable ranges, the higher the pressure the longer the tire wear and the less ultimate grip the tire can provide. Personally, I run 28-29 front, and 33-34 rear, and I'm running Pirelli Sport Demons. I can't get them to slip in dry conditions no matter how much I try, and the wear rate is acceptable at those pressures.

Rear shock preload comes from the factory in the softest setting (least preload). Tune to taste. With the specs you gave, if I had to pick a setting out of the air, I'd choose the middle position to start with (so position 3 of 5). I think the stock setting might be a little light and you'd find the bike feels a little more planted if the shock were slightly stiffer. It won't be a night and day difference, and it's not like your bike is currently unsafe at the existing settings and will become safe at position 3. It's more of a preference and how the bike feels to you with this range of changes.

It was a pain in the ass for me to change the preload with the tool they give us in the factory tool kit. It helps to put a rag around the handle so you can give more leverage as needed, and it may also help to remove the plastic chain guard (2 screws) while you're making the change. It's been posted here and elsewhere that removing the chain guard is unnecessary, and it very well may be unnecessary once the preload adjuster is broken loose the first time, but for me and our ninjette at least, I needed to remove it the first time.

Go for a ride with the new settings, and decide if it has changed the bike in a way that made it more or less comfortable for your riding style. If it's not perfect, change it and try it again. Rear tire pressure and rear shock adjustment can have an interaction; the harder you have the tire, the shock may be able to be run at a slightly less hard setting, but at that point it gets to some real fine tuning. (and actually, playing with tire pressure has more of an effect on compression and rebound settings, which aren't adjustable on our rear shock anyway).

Sailariel · January 5th, 2009, 04:42 PM

Alex, Thanks a million! Motorcycles have come light years since my Dunstall Norton. The inacessibility of things is amazing, e.g. something as simple as ,changing a light bulb becomes a major project. The bike tips over because you did not insure the centre stand could not sink into the dirt--$600.00. Yikes! It will take me a while to get up to speed. The upside, of course is that the engineering is so far advanced that the service intervals are farther apart.

NJD022588 · January 6th, 2009, 12:49 AM

Yeah, I was able to easily change the rear preload settings without removing anything. I use the tool without the extension handle thats given in the tool pack and approach the bike from the right side since there's more open room for arms to reach in (under the rear brake reservoir). I actually attach the tool on the left side of the preload adjustment and, if I remember correctly, just pull the handle towards my body to tighten/go up/increase preload.

Sailariel · January 6th, 2009, 01:38 PM

Thanks for the Heads Up. I actually have a Bottom Bracket wrench (Bicycle tool) that is identical but has a 12"handle. I suspect that the shock will "surrender"very quickly.

kkim · January 6th, 2009, 02:08 PM

I don't think a spanner tool with a longer handle will fit in there to adjust the shock. If I remember correctly, the tool from the tool bag was a perfect fit, but try it and let us know if the longer handled tool works.

wear gloves when you try to adjust the shock preload.

Sailariel · January 6th, 2009, 02:16 PM

You are right . The wrench is entirely too big. Incidentally, I checked my swingarms and there is no sticker in sight. Must be the idiot dealer took them off. Owner`s manual says they should be there. I am so glad that I no longer have to deal with him. He can sell his snowmobiles and stay away from bikes.

kkim · January 6th, 2009, 02:23 PM

Are you sure about the sticker on the swingarm? It's on the side of the swingarm on the left hand side, but it's a gold lettered sticker on a black swingarm... very difficult to see, even if you are looking for it. I had to get on my hands and knees to be able see and read it.

Sailariel · January 6th, 2009, 03:01 PM

Kelly, The left swingarm is clean--no stickers, just my wax job. Who knows, maybe the factory forgot to put them on. Anyway, I can always read what it says in the Owner`s Manual now that I have one.

January 5th, 2009, 03:19 PM	#1
Sailariel ninjette.org certified postwhore Name: Alex Location: Belfast, ME Join Date: Jul 2008 Motorcycle(s): 2010 Honda NT-700-V, formerly, Green 2008 Ninja 250R Posts: A lot.	Tyre Pressure and Suspension adjustment Alex, I read your very informative narrative on the Literbike crash and how a combination of confounding variables could have been the culprit. My 08 Ninjette is completely stock (and will stay that way) I can not find anything in the Owner`s Manual or Shop Manual that tells me what tyre pressure I should be running. I have the OEM Dunlops and have been running 32Psi in front and 36Psi in the back. I weigh 195. The bike seems to handle well and I basically ride secondary roads at 55 to 65mph. Also, where does Kawasaki set the rear shock at the factory? The book is quite vague as to where it should be set. When I take trips, I carry about 30lbs of luggage in a tank, tail, and saddle bags. That gives me a laden weight of approximately 225lbs. What would you recommend as the proper tyre pressure? Also which notch should I set my shock absorber on? Thank you in advance. Alex II

January 5th, 2009, 03:56 PM	#3
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Hi Alex - With tire pressure and suspension adjustment, they are two areas where there is never going to be a single correct answer, with all other answers being incorrect. By their very nature, the choices must come in ranges, and people's preferences will play a role in what they feel works best for them. With that caveat, here's what I think. Stock tire pressure, recommended by Kawi, measured cold, is 28 psi front and 32 psi rear. Anywhere within +/- 4 of those numbers won't result in a terribly unsafe motorcycle, but at the extremes the rider would likely notice a mushiness (on the low end) or a harshness (on the high end). Within reasonable ranges, the higher the pressure the longer the tire wear and the less ultimate grip the tire can provide. Personally, I run 28-29 front, and 33-34 rear, and I'm running Pirelli Sport Demons. I can't get them to slip in dry conditions no matter how much I try, and the wear rate is acceptable at those pressures. Rear shock preload comes from the factory in the softest setting (least preload). Tune to taste. With the specs you gave, if I had to pick a setting out of the air, I'd choose the middle position to start with (so position 3 of 5). I think the stock setting might be a little light and you'd find the bike feels a little more planted if the shock were slightly stiffer. It won't be a night and day difference, and it's not like your bike is currently unsafe at the existing settings and will become safe at position 3. It's more of a preference and how the bike feels to you with this range of changes. It was a pain in the ass for me to change the preload with the tool they give us in the factory tool kit. It helps to put a rag around the handle so you can give more leverage as needed, and it may also help to remove the plastic chain guard (2 screws) while you're making the change. It's been posted here and elsewhere that removing the chain guard is unnecessary, and it very well may be unnecessary once the preload adjuster is broken loose the first time, but for me and our ninjette at least, I needed to remove it the first time. Go for a ride with the new settings, and decide if it has changed the bike in a way that made it more or less comfortable for your riding style. If it's not perfect, change it and try it again. Rear tire pressure and rear shock adjustment can have an interaction; the harder you have the tire, the shock may be able to be run at a slightly less hard setting, but at that point it gets to some real fine tuning. (and actually, playing with tire pressure has more of an effect on compression and rebound settings, which aren't adjustable on our rear shock anyway). __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

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January 5th, 2009, 03:42 PM	#2
kkim Join Date: Nov 2008 Posts: Too much.	Recommended pressures are on a label on your swingarm, right below your chain. 28f/32r. I ran 28/28 f/r with the stock tires. As far as rear preload, with the luggage weight, I would bump it up one notch from your "regular" shock notch setting. To determine what your "regular" shock setting should be (I don't know your weight), I kept bumping my shock up one notch at a time until I felt it was too stiff for my type of riding and backed it down one notch. The shock comes set at the lowest of the 5 settings from the factory. All tools needed to adjust is in your tool kit that came with the bike.

January 5th, 2009, 04:42 PM	#4
Sailariel ninjette.org certified postwhore Name: Alex Location: Belfast, ME Join Date: Jul 2008 Motorcycle(s): 2010 Honda NT-700-V, formerly, Green 2008 Ninja 250R Posts: A lot.	Alex, Thanks a million! Motorcycles have come light years since my Dunstall Norton. The inacessibility of things is amazing, e.g. something as simple as ,changing a light bulb becomes a major project. The bike tips over because you did not insure the centre stand could not sink into the dirt--$600.00. Yikes! It will take me a while to get up to speed. The upside, of course is that the engineering is so far advanced that the service intervals are farther apart.

January 6th, 2009, 12:49 AM	#5
NJD022588 ============ Name: Nick Location: Occoquan, VA Join Date: Nov 2008 Motorcycle(s): '09 Ninja 250R Posts: 518	Yeah, I was able to easily change the rear preload settings without removing anything. I use the tool without the extension handle thats given in the tool pack and approach the bike from the right side since there's more open room for arms to reach in (under the rear brake reservoir). I actually attach the tool on the left side of the preload adjustment and, if I remember correctly, just pull the handle towards my body to tighten/go up/increase preload.

January 6th, 2009, 01:38 PM	#6
Sailariel ninjette.org certified postwhore Name: Alex Location: Belfast, ME Join Date: Jul 2008 Motorcycle(s): 2010 Honda NT-700-V, formerly, Green 2008 Ninja 250R Posts: A lot.	Thanks for the Heads Up. I actually have a Bottom Bracket wrench (Bicycle tool) that is identical but has a 12"handle. I suspect that the shock will "surrender"very quickly.

January 6th, 2009, 02:08 PM	#7
kkim Join Date: Nov 2008 Posts: Too much.	I don't think a spanner tool with a longer handle will fit in there to adjust the shock. If I remember correctly, the tool from the tool bag was a perfect fit, but try it and let us know if the longer handled tool works. wear gloves when you try to adjust the shock preload.

January 6th, 2009, 02:16 PM	#8
Sailariel ninjette.org certified postwhore Name: Alex Location: Belfast, ME Join Date: Jul 2008 Motorcycle(s): 2010 Honda NT-700-V, formerly, Green 2008 Ninja 250R Posts: A lot.	You are right . The wrench is entirely too big. Incidentally, I checked my swingarms and there is no sticker in sight. Must be the idiot dealer took them off. Owner`s manual says they should be there. I am so glad that I no longer have to deal with him. He can sell his snowmobiles and stay away from bikes.

January 6th, 2009, 02:23 PM	#9
kkim Join Date: Nov 2008 Posts: Too much.	Are you sure about the sticker on the swingarm? It's on the side of the swingarm on the left hand side, but it's a gold lettered sticker on a black swingarm... very difficult to see, even if you are looking for it. I had to get on my hands and knees to be able see and read it.

January 6th, 2009, 03:01 PM	#10
Sailariel ninjette.org certified postwhore Name: Alex Location: Belfast, ME Join Date: Jul 2008 Motorcycle(s): 2010 Honda NT-700-V, formerly, Green 2008 Ninja 250R Posts: A lot.	Kelly, The left swingarm is clean--no stickers, just my wax job. Who knows, maybe the factory forgot to put them on. Anyway, I can always read what it says in the Owner`s Manual now that I have one.