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Air Forks on 650L -- Air in or out?

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I just got an all original '07 650L. I will be putting it on a diet and getting it more trail worthy. When I bought it, the guy couldn't find the manual (of course). Are the schrader valves on the top of the front forks designed to add air for a cushy ride, or let air out - like the air bleeder screws on regular dirt bike forks. If it matters, I weigh 225 without gear and will be riding some pretty hard core dual sport stuff.

Also, if you do the battery reloacation under the seat, will an XR600 side panel fit right on.

Thanks.

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The forks are designed to run 0-15psi of air. (Add air if bottoming out, etc) They are not like CR forks, that need to have air bled. They are 'adjustable' w/air. Best to raise frt wheel off ground before adding air. And...best to use a bicycle air pump, as to not add too much pressure at once. I have a XRR, so dunno about the side panel deal. Im sure a search in this forum will get the answer you are looking for.

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THe manual states that you can put up to 6#'s of air in the shocks. From what I've read on here, nobody does it. YOu can use it to bleed any excess air out of the forks.

Does this bike come with stock fork/shock springs? I weigh exactly the same as you and on the road the L is fine with the stock stuff, however off road, the stock springs rear their ugly head. With woops, I was all over the place. But right now I'm getting the bike resprung, the rear shock revalved and I'm going to install a RSW fork brace. It should be done in about two weeks and I can't wait to see how it will handle the same trails I rode last year. I'm also upgrading the pegs to some IMS super stock. They are much wider than stock and since I buggered my left one on a tree last year, I figured, why not upgrade to a wider one.

BTW, I'm going with Eibach 47 fork spring w/ 10 weight oil and an Eibach 12 spring on the shock.

As for the XR600 side panel, I think I read on here that it is a direct fit.

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Yes,

Everything is bone stock. So far I just blasted a few dirt roads and some sand washes. I am going to gear it WAY down, put on some real tires and get a little rowdier. I'll play with the air.

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cardoc, 0-6(max) psi is correct. 0 most of the time add 4-5 psi to stiffen it up, see what you think. Where in Ct do you ride? Ive got a slightly "moded" 05 in Storrs.

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Dittos on the forks. They are setup to run air up to 6 lbs. My shop guy has always recommended against it though. I'm at 215lbs. and my forks are setup with 49kg Progressive springs.(`89 CR500. Same forks but you can get heavier springs on that application). Gold valves setup for woods. SRC forkbrace which is no longer avail. GET SOME KIND OF FORKBRACE!! Consider it safety equipment. You start pushing that pig and the stock forks will flex so bad that you will end up on your head with a separated shoulder and a 300 lb. porker resting comfortably on you. (Trust me). Mine's geared one notch lower than stock XR600 gearing. Electrics can be repackaged with a small atv battery stuffed into your opened up airbox with the XR600 spec foam filter. Stuff the rest of it under your tank and dump the suitcase and get your XR600 sidepanel. Your friends will be amazed. I went with an Eibach spring in the back and left the shock alone. Stock damping adj. is adequate for me. You can Email me for more. I've had mine for 12 yrs. now

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I went to my local Harley shop and bought a low pressure shock pump for a Road King. They have a nice pump that is ranged from 0 to 60 lbs in 1 lbs increments. It also has a bleed valve on it to get the pressure just right. I think it was around $40 or so. I bought it when I first got me XR250L to help stiffen up the front.

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these are oldskool forks so playing with the air pressure is fine...i used it with sum success at around 5psi... :)

...i currently have sum preload spacers (30mm) but they will be removed and/or cut in half...too damn harsh on the hands & wrists

the other option is raising the oil level...

the air pressure & changing the oil level are both "progressive" adjustments...meaning as the forks are further compressed the effective spring rate increases...

...increasing ether also helps to prevent bottoming...likewise increasing the compression.

:banghead:

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bleeding air out of forks is needed for any bike really, temp changes affect them so its never a bad idea to have them up on a stand and let them equalize to outside, take a 40degree winter day to a 105degree summer hot one, big difference! do like you mentioned on MX bikes and equalize them out if you want them at 0psi and if you wanna add a few try it out

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Great info guys. I live in Arizona - I don't why it shows Ct. I'll change that. I can't believe how much info and upgrades you guys have for these BRPs. I can't wait to start tinkering and see what this baby will do. I think the battery relocate and XR600 side panel is a good mod. What about pipes? I bought a Pro Circuit pipe but had to return it as it wouldn't between the flanges on the head pipe. It seams everyone is using FMF.

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Thanks for the info on the forks, mine is a '94.

I went to a place called Durhamtown in crawfordville Ga. Saturday, and rode for a few hours. I have had my L pig for about 4 years and absolutely love my pig. I however do not like the spongey feel of my forks.

Aside from adding air can a thicker/heavier oil be added?? or will this screw up the valving?

Being an old school xr ride it (like it came from the factory) fast person, i have never screwed around with any suspension before and don't want to screw up my pig!

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Thanks for the info on the forks, mine is a '94.

I went to a place called Durhamtown in crawfordville Ga. Saturday, and rode for a few hours. I have had my L pig for about 4 years and absolutely love my pig. I however do not like the spongey feel of my forks.

Aside from adding air can a thicker/heavier oil be added?? or will this screw up the valving?

Being an old school xr ride it (like it came from the factory) fast person, i have never screwed around with any suspension before and don't want to screw up my pig!

I think the stock fork oil is either 5 or 7 weight. When I had my forks off the last time I changed the oil out to Amsoil Synthetic ATF fluid and it really helped with the "spongey" feeling. You may have to go out a few more clicks on the adjusters with ATF (I have mine at 10 clicks out as apposed to the stock setting of 3), but overall I like the feel of ATF over "normal" fork oil. The front end definitely isn't spongey anymore.

I may also point out that my bike is set up for Supermoto, so the majority of my riding is on pavement. :busted:

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these are oldskool forks so playing with the air pressure is fine...i used it with sum success at around 5psi... :busted:

...i currently have sum preload spacers (30mm) but they will be removed and/or cut in half...too damn harsh on the hands & wrists

the other option is raising the oil level...

the air pressure & changing the oil level are both "progressive" adjustments...meaning as the forks are further compressed the effective spring rate increases...

...increasing ether also helps to prevent bottoming...likewise increasing the compression.

:banana:

Update: since i have my bike set up for woods/hare scramble riding i have removed the preload spacer...running a 10mm higher oil level to prevent bottoming and zero psi air pressure...

...saw a pretty trick setup on a KTM 300 XC-W this weekend...along with having the forks revalved this bike had "remote" fork air reservoirs :banana: this allowed it to have a higher oil level to prevent bottoming AND keep a larger airspace which acts as a progressive air spring. :thumbsup:

:banana:

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Does the ATF have any bad effect on the seals ( will it shorten the life span ) ???

Nope, it's probably better for the seals than Fork Oil. The reason being is that it has rubber conditioners and detergents in it that are designed to keep all the little rubber o-rings, diaphragms and passages in an automatic tranny in good shape in a high heat, high pressure environment over tens of thousands of miles. :busted:

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I went up one weight on the front fork oil and raised it 10mm, no air. If you are on the heavy side geared up, I would look into replacing the springs.

I changed my gearing to 14/48 so when I let the clutch out in 1st it will idle at a walking pace.

I have a Cobra ISDE pipe, I don't even know if they make them anymore... It was supposed to be the quietest pipe available (after a choked up Supertrapp) but it's still pretty LOUD.

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