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Help a new guy understand the XR250 suspension

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So I bought this 2001 plated XR250 a few months ago. I am new to dirt bikes and so far I really like this bike. I think it is great bike for a new to dirt guy like myself. I have slowly been cleaning it up a little and changing out parts that are in need (seat cover, bars, sprockets, chain, etc..) minor stuff. The previous owner said the suspension had been set up by local suspension guy to his weight and style. Him and I are the same weight if that helps but he has been riding as long as I have been alive (40 yrs).

I want to learn more about how these suspensions work but the manual he gave me with the bike really only talks about replacing parts and nothing on set up. I see the rear shock has 2 adjusters (one on the canister and one below the spring), what do these do?

I dont know what to feel for as of yet when Im riding but I am learning as I go.

If anyone knows of a good guide for understanding the XR250 suspension I would love to know where to find it.

Thanks

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On the rear shock, the clicker on the reservoir is for compression. The bottom adjuster on the clevis end of the shock is for rebound.

On the forks, the bottom adjuster is compression and the adjuster in the fork cap is rebound.

There's lots of info on how suspension works and tuning in a Google search.

Here's some to get you started.

http://www.off-road.gr/article17.html

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On the rear shock, the clicker on the reservoir is for compression. The bottom adjuster on the clevis end of the shock is for rebound.

On the forks, the bottom adjuster is compression and the adjuster in the fork cap is rebound.

There's lots of info on how suspension works and tuning in a Google search.

Here's some to get you started.

http://www.off-road.gr/article17.html

Uhh, dude, you got it wrong. XRs don't have rebound damping on the forks. They just have compression damping on the bottom and an air bleed plug in the fork cap.

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Uhh, dude, you got it wrong. XRs don't have rebound damping on the forks. They just have compression damping on the bottom and an air bleed plug in the fork cap.

Nope, he's quite right, well your both right.

'96-'04 XR400R and XR250R forks have Compression AND Rebound Adjustments.

'91ish-'95 XR250Rs are like your talking about

Pre-'91 XR250R and '91-'96 XR250L have no external adjustment other than the Schrader Valve which the manual recommends 0-6psi depending on conditions/ load.

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On the rear shock, the clicker on the reservoir is for compression. The bottom adjuster on the clevis end of the shock is for rebound.

On the forks, the bottom adjuster is compression and the adjuster in the fork cap is rebound.

There's lots of info on how suspension works and tuning in a Google search.

Here's some to get you started.

http://www.off-road.gr/article17.html

First, thanks for clearing that up I really was going to ask about all the adjustments and start tuning my susp. I had read some stuff from Dwight and you about setting free sag. But, I looked at the link you posted and it makes no sense, plus it is written for a tuned suspension?

If the bike tops out or has less than 3/4 of an inch of sag then the spring is too soft! If the bike sags drastically under it's own weight, then it has too stiff a spring rate.

This makes no sense to me?

I'd like a step by step for my bike.

So, for an 01 XR400, I would put it up on a center stand and measure sag front and rear.

Then get on the bike on the ground and measure sag front and rear.

Then adjust COMPRESSION settings for both ends to have 30% sag front, 33% sag rear?

What are the rebound settings for? What will it feel like or how will it act if the rebound is too soft or harsh? How many 'clicks' do my shocks have? What am I looking for as I adjust each of the four settings?

I need detailed instructions. 👍

BTW my bike was probably set up as harsh as possible, and it does seem harsh on the front. I'd like to get this to 'baseline' for my weight, and I don't really know how to get there although I understand thesome concepts. I need the mechanics of it. I weigh in about 190 stock myself.

I've gone over some stuff on the web, in the susp section here at TT, I'm just trying to get it all straight right now.

BTW I'm not trying to hijack, I'm going on the assumption that the 250 and 400 suspensions are the same. Sorry OP if I'm messing up your thread.

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Race sag is the amount the suspension sags with a rider aboard. On the XR400 rear you want between 3.5"-4". You adjust spring preload to achieve this.

Free sag is the amount the suspension sags under the bikes own weight. You take that measurement AFTER you have race sag set. If after getting race sag set to spec, free sag is less than 3/4"-1" or no sag at all, that means you had to preload the spring too much to get it to support your weight and achieve race sag spec.. It may support you when you're on the bike and have the proper race sag when adjusted like that, but when you climb off it, the spring is under so much preload it easily supports the weight of the bike alone, so there is little to no free sag. So the spring rate is too soft for your weight.

On the other hand, if free sag was more than an inch AFTER getting race sag set, that means you had to remove as much preload from the spring as possible to get it to sag enough for your weight to achieve the race sag spec, meaning the spring rate is too stiff for your weight.

With a bike on a stand, there is no sag. The suspension is completely extended(static). Take those measurements. From the axle bolt to someplace on the frame/bodywork.

Then on the ground with rider aboard, feet on the pegs. Take measurements from the same points as before.(get a helper) Subtract rider aboard figure from static figure. That's race sag. Adjust spring preload as needed to achieve the spec.

The compression clicker adjustments have nothing to do with sag. The springs have sole responsibility in supporting the bike and rider.

Compression adjustments have to do with how much/easily the suspension valving allow the suspension to soak up hits. How much the suspension "compresses".

Rebound controls how slow or fast the suspension valving lets the suspension return to its normal length after compressing from a hit.

There are S and H markings at the adjusters. S= softer/faster action and H= harder/slower action.

Getting the two aspects to work well together is kind of a timing thing, depending on the type terrain you're riding. You want enough compression to soak up the terrain and provide a comfortable/non harsh ride, while having the rebound set fast enough to get the tire back to the ground fast enough so the suspension can soak up the next hit.

You can easily get an idea what each of the compression and rebound adjustments do at home in the garage. Set the rear compression and rebound adjusters to full soft. Now forcefully push down on the seat. See how easily it compresses and comes back up. Now turn just the rebound in several clicks. Push the seat down again to see how much slower it is allowing the suspension to return.

The forks spring preload is measured and set/adjusted internally. For race sag you're looking for about 1.5".

When adjusting your suspension, it is usually recommended to set the clicker adjustments in the middle of their range as a starting point to fine tune "from". So if from full in to full out on a clicker adjustment you have 22 clicks, set it to 11 from full in. Go ride and see how it feels. Ride the kind of terrain you're going to see the most.

Keep reading. You'll learn about "packing" and "wash out" and other phenomena and how to alleviate each.

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Nope, he's quite right, well your both right.

'96-'04 XR400R and XR250R forks have Compression AND Rebound Adjustments.

'91ish-'95 XR250Rs are like your talking about

Pre-'91 XR250R and '91-'96 XR250L have no external adjustment other than the Schrader Valve which the manual recommends 0-6psi depending on conditions/ load.

??? 👍 I have a '01 XR250R with the stock suspension, and it does not have a screw to adjust rebound for the forks. Nowhere in either of my manuals (owners and service) does it talk about rebound damping adjustment for the forks. Do you guys have USD converts or something? And if these bikes DO have adjustable rebound, could you please direct me to where it is?

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I have owned three post-'96 XR250s, none of the three had rebound adjusters, only compression.

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I have 96 xr250 and 2000 xr400 and only air bleeders on the top of the forks.

Ok, we have two xr400's. 2000 and a 2001. I did put usd forks on mine 2000, but my stockers and the 2000's forks have compression and rebound adjustment screws. if you look in the owner's manual, it talks about adjusting the rebound or the compression. Believe me, as I have consulted it before.

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Ok, we have two xr400's. 2000 and a 2001. I did put usd forks on mine 2000, but my stockers and the 2000's forks have compression and rebound adjustment screws. if you look in the owner's manual, it talks about adjusting the rebound or the compression. Believe me, as I have consulted it before.

My 2000 XR400 has both comp and rebound on the forks too.

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...? I think I should eat my words. 👍

I knew the XR400 had compression and rebound adjusters front and rear and I guess I assumed that Honda would do the same for the XR250R when the forks were upgraded in '96.

Looks like the XR250s never got rebound adjusters on the forks:

http://www.motorcycle.com/manufacturer/honda/living-with-hondas-xr250r-15052.html

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So would a 96 up XR250 be a good candidate for XR400 forks? Since they are fully adjustable and bigger? What would be needed to swap, forks and triple clamps or whole front end? Thanks Jim 👍

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So would a 96 up XR250 be a good candidate for XR400 forks? Since they are fully adjustable and bigger? What would be needed to swap, forks and triple clamps or whole front end? Thanks Jim 👍

in terms of adjust-ability, i would think they would be the next best option to USD forks. probably one of the easier swaps.

According to the dennis kirk bearing cross reference, the steering stem bearings are the same on the xr400 and on the xr250, so it should be a pretty easy swap unless the stems are different lengths between the two bikes. It might mean the use of the xr250 stem in the xr400 lower clamp if that is possible.

http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=505745&store=Main&catId=&productId=p505737&leafCatId=&mmyId=1933

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So would a 96 up XR250 be a good candidate for XR400 forks? Since they are fully adjustable and bigger? What would be needed to swap, forks and triple clamps or whole front end? Thanks Jim 👍

Remember, The XR400R forks aren't "fully" adjustable just more adjustable. More modern cartridge forks will have 1) Rebound and 2) Low Speed Dampening and 3) High Speed Dampening. The High Speed dampening on the XR400R forks can only be adjusted by means of taking the forks apart and playing with the shims (see shim stack mod)

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my 84xr250 only has a allen key bolt on the bottom and shcrader valve on top.

is there any differance in 250rf and 350re forks???

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Remember, The XR400R forks aren't "fully" adjustable just more adjustable. More modern cartridge forks will have 1) Rebound and 2) Low Speed Dampening and 3) High Speed Dampening. The High Speed dampening on the XR400R forks can only be adjusted by means of taking the forks apart and playing with the shims (see shim stack mod)

depends on which year of forks you get. Mine only have rebound and compression, not the high speed and low speed. mine are 2001 showa

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my 84xr250 only has a allen key bolt on the bottom and shcrader valve on top.

is there any differance in 250rf and 350re forks???

The allen on the bottom is for dissassembling the forks, not for adjusting. The scrader is the only adjustment your forks have (externally). It varies from year to year but you can put some air pressure in the forks according to honda to make it ride better. I never noticed a huge difference when I did on my 250L, a little but not much. Not sure about the 250/350 difference.

depends on which year of forks you get. Mine only have rebound and compression, not the high speed and low speed. mine are 2001 showa

...I would have thought the newer MX forks would have that. I know the RM125/250, DRZ400E and later DRZ400s have the high speed dampening on the forks and shock. I though that started in the late 90's.

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