XR400 'Spring Seat'

[KnackeredMk1]

I've just taken apart 2 sets of XR400 forks that I'm using to upgrade my CRM. In both sets there are no 'spring seats'; the part that sits on top of the spring and under the nut at the top of the damper rod. The nut locks the damper rod into the fork cap.

The 'spring seat' is listed in the Honda UK parts manual and the official Honda workshop manual.

Is this usual practice and do all UK XR400s come from Honda like this? The effect must be to take off about 30mm of preload. Is this the reason why some people on this site and others add preload spacers?

Also the part numbers for the springs do not change from the RT to R4. So the spring rate change only happened in the US?

[jasonbc]

I've just taken apart 2 sets of XR400 forks that I'm using to upgrade my CRM. In both sets there are no 'spring seats'; the part that sits on top of the spring and under the nut at the top of the damper rod. The nut locks the damper rod into the fork cap.

The 'spring seat' is listed in the Honda UK parts manual and the official Honda workshop manual.

Is this usual practice and do all UK XR400s come from Honda like this? The effect must be to take off about 30mm of preload. Is this the reason why some people on this site and others add preload spacers?

Also the part numbers for the springs do not change from the RT to R4. So the spring rate change only happened in the US?

Below is a suspension drawing from a 99 xr400ry the only difference is that this model uses shorter springs and a spacer on top of the spring instead of longer springs




It's clearly there number 5 and that is from a genuine honda book not haynes or clymer

[KnackeredMk1]

I have recourse to Honda parts manuals all the way through from the RT to the R4 and it is in all of the diagrams. It is also in the official Honda service manual.

I am asking the question to establish if this part is generally ommited in UK spec XR400s or by some aftermarket modification they have been removed from both sets that I have.

[KnackeredMk1]

I'm not sure if you meant this but the part you have circled (12) is an oil lock that goes at the bottom of the fork not a spacer for the spring.

[jasonbc]

I'm not sure if you meant this but the part you have circled (12) is an oil lock that goes at the bottom of the fork not a spacer for the spring.

That was a drawing for me that the dealer did for me it's a spacer that goes ontop the spring,which is why he marked it "top". When i took it a part it was on top the spring but the manual i have for an rt didn't show it so i took it to my honda dealer to confirm top or bottom and it was top as i said other earlier models use longer springs this uses shorter springs and a spacer

[KnackeredMk1]

As a newbee I hesitate to contradict you but I have all the parts diagrams for the XR400 RT - R4 and they all say that the part illustrated as 12 is the oil lock piece (as does your diagram above).

The illustration in the Honda manual shows the parts in a slightly different placing on the page but again shows this part as the oil lock piece. None of the diagrams I have seen show a spacer that goes on top of the spring but all show the spring seat.

Are all the official Honda documents wrong? Have I just happened across two sets of forks where the spring seats have been removed. - For SM setup perhaps?

Anyway, I'm ordering a set tomorrow.

[jasonbc]

As a newbee I hesitate to contradict you but I have all the parts diagrams for the XR400 RT - R4 and they all say that the part illustrated as 12 is the oil lock piece (as does your diagram above).

The illustration in the Honda manual shows the parts in a slightly different placing on the page but again shows this part as the oil lock piece. None of the diagrams I have seen show a spacer that goes on top of the spring but all show the spring seat.

Are all the official Honda documents wrong? Have I just happened across two sets of forks where the spring seats have been removed. - For SM setup perhaps?

Anyway, I'm ordering a set tomorrow.

All i know is mine went back together the same way that they came apart and th eoil lock peice in the rt book is no.11 in drawing

[416cc]

I too looked at the fiche on CMSL honda front fork partsmanual fiche xr400r 99 xr400 & part number 12 is the part that sits on the bottom of the damper rod as the oil lock piece. Part number 5 is the spring seat. These parts are shown very clearly in both my Haynes & Clymer manuals. It does seem a little strange that part number 5 should be missing off both sets of forks.

When I replaced the standard fork springs on my '97 XR with some 0.46kg items from Race-Spec Race Spec UK - Motocross Fork Springs, Spares, Accessories, Parts and Clothing online it made the world of differance & stopped the skittishness that was felt with the OEM ones. As yet, although I have made up some preload spacers in various thicknesses, I havn't found a need to use them with the replacement springs.

Although I used some top quality Ohlins 5w fork oil, i've heard that they source their stuff from Morris Lubricants Morris Lubricants & triple the price.

[KnackeredMk1]

Thanks 416cc.

If I may ask what weight you are? Did your forks have the spring seat? And lastly did you do the compression damping mod that I have heard so much about - I.E. did you remove 6 of the 12 shims from the compression damping stack?

[416cc]

I'm 14 stone if i've not been on the beers for a while. It may well have been that the original springs had sagged a bit before I owned it, so replacing the springs made a very worthwhile differance in front end control.

I did modify the compression damping device by replacing it with one from Race-Tech in the USA, which are now available from PDQ over here. This replacement device makes the clickers actually do something, whereas it's difficult to feel if you've actually changed anything with the standard device. The RT device comes with excellent instructions & plenty of spare shims so's you can fine tune the device to your own needs. Using a quality fork oil also goes a long way to making the clickers work properly. RACE TECH PRODUCT SEARCH


Once the front end was sorted, it made the back-end of my XR feel pretty vague...so I bought an Ohlins for £300, which allowed me to go about 25mph faster on the rough stuff...which was more cost effective than having engine work done.

And yes, my forks did have the spring seat.