650g fork rebuild parts advice

[Charlie G]

I've read a few threads and think I know what parts I should get but before I order, I like input from someone if there is any thing else in the way of Suzuki parts I'll need. I think I've decided on Sonic replacement springs. I would have liked to put in emulators but that's not in the cards in the near future. Thanks for your help.


I plan on ordering Part#s 7 seals, 18, 28,31,12, 21, and 5





Charlie G

[salty_monk]

Isn't that a 35mm fork? I would chop the stock springs to give you an equivalent straight weight spring to a sonic and spend your money on some emulators from MikeXS for $50....

I have just done exactly that with some 1100 forks for the skunk and its worked out great.

I can coach you through chopping the spring and show you the online tool for calculating rates etc.

I took the stock 1100 spring from 28lb to 43.5lb from memory (Sonic 0.8 eq), using a mikes xs emulator in an adaptor ( you wouldn't need adapter with a 35mm fork) and they are working great so far.

If you are lucky you might even get away with just getting rid of spring no. 27 on the fiche and not even have to chop the other one as you're not typical American build
I did that to great effect on a 550E.

[Charlie G]

Isn't that a 35mm fork? I would chop the stock springs to give you an equivalent straight weight spring to a sonic and spend your money on some emulators from MikeXS for $50....

I have just done exactly that with some 1100 forks for the skunk and its worked out great.

I can coach you through chopping the spring and show you the online tool for calculating rates etc.

I took the stock 1100 spring from 28lb to 43.5lb from memory (Sonic 0.8 eq), using a mikes xs emulator in an adaptor ( you wouldn't need adapter with a 35mm fork) and they are working great so far.

If you are lucky you might even get away with just getting rid of spring no. 27 on the fiche and not even have to chop the other one as you're not typical American build
I did that to great effect on a 550E.

Yes their 35mm forks. I was hoping to get some input from you, considering our mutual stature. I think I'll do as you sujest, as it would help me work toward getting a fork brace. What about the parts I'm planing on getting? Have I got all the bases covered with the ones I listed? This is my first frok rebuild. I'm not quite grasping how they work, but I know when I take them appart it will become evident. I'll check out mikes XS emulators and scratch my head over how they install. Thanks.

cg

[Johnny Drummond]

The best way I found to split the slider(NO.20) from the stantion(NO.3&4) is to get some thin ply and hold the stantion horizontally in a vice(after removing the oil,springs,circlip(NO.9),and fork seal(NO.6?),then buy a bolt about 50/60mm in length that has a 19mm hex head and 2 nuts.Lock the nuts together at the end of the bolt and compress the slider fully and with around 500mm of extensions onto your ratchet/t bar put the bolt down the centre of the slider(NO.20) and slowly turn it until it clicks into the end of the damper rod(NO.23 in the diagram).Get an 8mm hex key and take off the end cap(NO.13) and use the key to loosen the bolt(NO.11) while holding tightly to the ratchet/tbar,this might take some effort as the bolt seems to have some kind of locking compound applied at the factory-am I making sense,cos if I am it would be a first.Johnny

[Charlie G]

Dang...I followed that. Actually I watched Sandy and azr take some forks apart last fall and azr left me the set up to reach that bolt in the forks. Sounds a bit tricky. Alot going on while getting the froks apart. It would be better if I had a second person helping me out. It'll take me a couple of weeks to get the parts but, do you think you could come over one weekend and give me a hand? I have room for everyone...even Freckles

cg

[Steve]

Here is the tool you need.





1/2" all-thread rod, 2 feet long, with four nuts. Cost is about $6.

As for your parts list, looks good to me.

.

[eil]

Those forks look mostly similar to mine. Yours actually has a second smaller spring where mine had a spacer.

Anyways, taking apart the forks is not a huge deal. If you already have the tool to keep the damper rod from rotating, you're good to go. The 8mm bolt on the end of mine did not have any threadlock on it. (Although I applied some upon reassembly.) Once that's out, everything comes apart easy peasy.

Only difficulty I had with mine was that the OEM fork seal didn't want to come out. It was in there quite good for 33 years and had no intention of leaving. Eventually got it out, but not without a whole lot of sweating, swinging, and swearing.

[salty_monk]

I've never needed a 28 or a 31 on any fork but I assume they are cheap....

Not taken apart that particular fork before but from the fiche 5 & 7 look like a spacer to me with 6 being the actual seal... unusual as the seal usually sits right under part 8.

I would also buy part 24 as they are cheap & are *sometimes* worn - depends on mileage & how the fork has been looked after.

Given that you have air caps on that fork you could try releasing circlip 9 & using a bicycle track pump or compressor to put pressure in the fork (After emptying it of oil, the springs etc) & you might find that the seal pops right out with a pop & a load of smelly oily air (tie a rag around it is my advice). You might need 150-180PSI before it goes though if they haven't been done for a while. This is a neat trick if you know the rest of the fork is in good shape & you only need to change the seal only.
Otherwise you can lever it out after releasing the bolt in the bottom and removing the fork tube. I use a piece of black waste pipe bought from Home Depot as a drift for putting the new seals in.

The most complex part about fitting emulators is drilling the damper rod. This "how to" is the best I've seen. The fork is remarkably similar to a GS fork: http://www.advrider.com/forums/showthread.php?t=130606

Once you get the springs out we can take some measurements & work out the spring rates etc. Basically need an accurate wire diameter, number of coils & "free" length (no compression on spring). You'll need that info for both springs in the fork & the length of any solid spacer that sits on top of the spring (doesn't look like there are any in this fork).

Dan

[Charlie G]

Emulators ordered. Number 7 dosen't look like a seal to me , but three parts dealers label it as such. All I can do is order it and hope it's the right thing. Parts 21 and 5 are my concern. I read on GSR that I should replace the bushings/guides and these are labeled (best as I can figure?) as being these parts. Combined they come to $50.00. Wanted to be sure before I order. I guess these forks, from one type of GS to the next are different and make it harder to identify parts.

I want to keep the air option and found that o-rings 28 &31 the key. I will use the compressed air trick. Sounds like fun (messy).


Thanks!

cg

[gustovh]

If the friction coating is worn off of 21 then replace it. Otherwise........
V

[Johnny Drummond]

what an offer!

Sounds good to me!,just let me find where I put the hacksaw and get my shotgun.........OH wait,there is an extradition treaty between the UK and USA isn't there.....DAMN,believe me if I could I would and I'd have that 1100 up and running as well,its real easy to get the seals done take your time and don't sweat it,Because of undersized pattern seals I changed them on one fork leg 3 times in 14 days.It cost me more in fork oil than time or hassle-someday buddy

[salty_monk]

I would be ready to replace 24 but you may well not need to, that is a plastic friction part.

as Gustovh says you can sometimes get away without replacing 21 as well.

[Charlie G]

I'm going to go ahead and order both. Randomly, the right fork leg gives off a vibration like a torque wrench reaching it's setting, or at least I think that's where it's coming from.

I'll get this stuff ordered and go from there. Thanks.

cg

[Charlie G]

Sounds good to me!,just let me find where I put the hacksaw and get my shotgun.........OH wait,there is an extradition treaty between the UK and USA isn't there.....DAMN,believe me if I could I would and I'd have that 1100 up and running as well,its real easy to get the seals done take your time and don't sweat it,Because of undersized pattern seals I changed them on one fork leg 3 times in 14 days.It cost me more in fork oil than time or hassle-someday buddy

It's the thought that counts.

cg

[Charlie G]

I pulled the forks off today and broke down the left hand fork. The 19mm nuts on the all thread dosen't work on this 650. The damper rod dosen't have any machining to recieve the 19mm nuts. The manual shows using somthing like a square tapered shaft to engauge the damper rod. I have a straight, easy out, fit in a scocket, with extension when the time comes. I assume I really only need this when I'm tightening the damper rod back down. My 6mm allen socket wouldn't reach the damper rod cap screw on the right hans fork, but I managed to break it free with a series of a 6mm x 1/4" bit for my drill, 1/4" scocket, extension, ratchet. Broke the RH damper rod loose, but haven't dissambled it yet. I'm leaving town on a job for a few weeks and am apt to forget the sequence of things, so I'll preserve one till then.

Salty Monk, when your through "working hard" with the gang in Chicago, I could use a discussion of what spring needs what.

Thanks for the help.

cg