Keep it in the family, DRZ250 Cartridge forks onto a DR650

I've managed to free up one bolt adjuster after soaking it for a week and some brute force by a friend with the right tools, but the 2nd adjuster is resisting all attempts to get it moving.

Some Googling also indicates that as usual we get shafted for parts in NZ. I've been quoted $214NZ for replacement adjusters, but WorldOfPowerSports.com lists the part as $86.33US each, thats about $106NZ at todays exchange rate.

http://fiche.worldofpowersports.com...zukidb&a=264&b=20&c=0-SUSPENSION---FRONT-FORK

Give it some heat, too.

I don't have anything to give it any real heat and time is running out before Christmas where I have a couple of multi-day trips to do and a 2500-3000km trip at the end of January so I'm going to reassemble the forks with only one compression adjuster working and fit them to the bike for the break, then review things next year.

I may be stuffed anyway as from what I can tell the part is no longer available from Suzuki, so unless I can find a wrecked set of DRZ250 or DR350 forks I may not be able to get another adjuster.

Does anyone know about reassembling cartridge forks, do you just pour the oil back in like a damper rod fork and do you have to do funky things with the cartridge? and does anyone know what grade and volume of oil is required. There's not much info out there that I can find on these forks.

USD open cartridges, you put your hand on the top of the fork tube and compress it to create pressure. This forces the oil in and the air out of the cartridge. Dunno about those RWU forks though - see if you can do something similar on assembly?

Otherwise try ask here, if you haven't already: Drz250 Thread

Hi guys,

Can't you just swap the fork lower legs between the 650 and 400, thus keeping the 400 internals and the 650 brake mount? Or is the base compression stack ass'y a different diameter thread? The lower legs, after all, are just an open tube - and if the the diameters and bushings are the same -

Regarding the spring rates, I'm at 160 lbs and what works well for me on my WR250r street bike at 300 lbs wet is the stock springs at .47 kg/mm (both on and off-road). I run .42's on my 220 lb dirt bikes. So, with the 350+ DR, I would think you're looking at at least .48's for any fairly aggressive off-road work, more if you're heavier than I am.

I'm following this thread because I'm thinking about getting a DR.

edit: The DR650 manual calls for 10 wt oil. With regard to the cartridges, to get the air out you slowly cycle them through the range of motion until you get a firm feel (cycling out the air bubbles). You can change the amount of travel by adding more oil for less travel & more firm toward end of travel (if you bottom too much, for example), and less oil for more travel, less firm toward end of travel. Always stay within the recommended oil volume range tho'.

No you can't, the diameters are different.

Box'a'bits came around this morning and gave me guidance on rebuilding the forks, he's had a bit of experience rebuilding forks recently while fitting WR forks to his R100GS http://www.advrider.com/forums/showthread.php?t=612774.

We disassembled the forks completely, cleaned everything out, fitted new seals and they are all reassembled again ready to go onto the bike.

I took the new forks for a run out to Ocean Beach last Sunday, it's a mix of gravel/dirt track and sand. plus about 90km of seal to get there.

The forks handled pretty well. They pogo'd a bit on the seal at 60km/h but were pretty good at 100km/h. I had all the adjustments wound right out so fully soft, except the stuck compression adjuster which is stuck at about 25% in. I'll have a play with them over the next few rides and adjust the tuning a bit but so far I'm happy.

Is the wheel balanced?

umm, I'll have to check. It's the stock DR650 wheel I was using with the original forks and it didn't do it with those.

Even without oil, it shouldn't do that.

Steering bearings too tight?

Steering bearings and clamps are original DR650 ones and weren't altered during the upgrade.

After going back and forth through the options for upgrading my '06 DR650, I've decided I like the DRz250 fork swap option the best. Reasonably cheap, simple, easy adjustment, reliable and most importantly an improvement.

Out of curiosity though, is there any difference internally between the lower fork tubes of the 250/650 when completely disassembled? Could the 650 bottom be used with the 250 cartridges, negating the need for a calliper spacer?

I didn't compare the lower fork tubes sorry so no idea.

reviving an old thread... Based on all the work here, can you elaborate on which wheels will bolt up to my 2001 DRZ250?

thanks!

The DRZ250 forks were used on the last few years of the DR350. 97-99 of the dirt version and 98-99 of the street. You can tell because of the 6 bolt rotor vs the weird 4 bolt rotor of the other years. Those wheels are a direct bolt on. The 89-99 RMX250 front wheel looks like a match too. You can use an older DR350 front wheel you just have to change the wheel bearing and center support tube as the 4 bolt rotored front wheel uses a smaller axle (14mm? vs 17?).


https://www.ebay.com/itm/1999-97-99...AOSwnRZbqF4K:sc:FedExHomeDelivery!96161!US!-1

Did this swap a couple of years ago with Eddie's help. Recently finished up a tutorial that should be helpful in revalving the forks and fabricating a relocation bracket.

https://drriders.com/tutorial-drz250-cartridge-fork-swap-t23930.html

Thanks for the props and the great writeup, you didn't take any pics of the shim stack disassembly, reassembly and shim stack?

I didn't include the exact formation of my shim stack since this was provided to me with racetech's calculator. Doesn't seem right to spread for free the result of their paid service.

I did keep the stock shim stack and valve intact so I could add that. Would be EXCELLENT to get the help of a more competent suspension tuner than me to work up recipes for various weights so that this mod can be easily done only by buying shims and reusing the stock valves. The stock valves look like good parts to me.

Fair call on the Racetech info. I was interested in seeing the makeup of the stock stack and what parts of it affect what parts of the stroke, or speed of the stroke, the shim stack is voodoo to me.

Reviving an old.thread. if one could swap the lower for tubes, this would be the easiest and cleanest solution. Has anyone confirmed?