CRF1000 Honda Africa twin fork re-valve procedure.

Ok, now that the rear is sorted, it was time to look at the front.

I looked into the pricier options, but frankly wanted to go el cheapo and try the re-valve, re-spring option.  I was also curious to the state of my fork tubes at a mere 4500km.
Link to picture gallery here: https://flic.kr/s/aHsmknkQRB
You can either read the write up, or go pic by pic, in order. I’ve described them as best possible.

First off, a big thanks, to Motociclo (aka Mr. S) from Adv rider.  He was extremely helpful both on his on going posts, and emails back and forth to answer various newb questions I had about my first shim stack job.  Both excellent posts below.  Hopefully the below, will further assist someone else.

Fork install
http://advrider.com/index.php?threads/fork-install-guide.1250293/
Fork revalve guide
http://advrider.com/index.php?threads/crf1000-fork-revalve.1242323/

I mainly tackled this job to get better feel from the front end, and the correct springs for my weight.

You will need the following to pull this off:

  • Honda manual.  Print out pages 17-14 to 17-21, for additional help, I printed out Mr.S write up on the revalve procedure
  • Fork spring compressor tool
  • Park tools AV-5 Spindle axle vice tool (or similar)
  • 45mm seal driver.  Turns out neither a 43, or 48 mm driver will do.  A 1/1/4 PVC pipe cut in half, does the job half assed!
  • Height measuring tool.  A ruler will do the job too
  • Shop rags, preferably the micro fiber blue jobbies
  • Some amount of skill/confidence
  • Honda seals (not recommended) $80 for the set including dust seals, Kawasaki seals part #  92049-0118 $24 for a set of seals, or SKF seals (pricy, $150 for the set including dust seals but excellent quality)

I’ll largely base this on pictures, and shit I learned along the way.

Start with one fork.

I chose the left leg.  Follow dis assembly as per manual.
IMG_3750

Run both pre load and rebound all the way soft. leave as is. 19mm wrench
19 mm for the pre load

Tape yer nut
Use some painters tape not to f. up the fork cap.

Let the fun begin!
IMG_3751

So here’s the business end of things:

fork internals

1-compression components, 2-rebound, 3, male fork bushing

Start with the rebound valve. You’ll need to remove the oil lock, in order to free the rebound valve from the cartridge. Don’t do this: Clamp above the oil lock
Clamp the rod above the oil lock.  Use a small terminating screw driver to peel back the peened portions of the oil lock. Once that’s done, give the oil lock a decent whack and it will come off. I’ll expose the circlip shown below.
IMG_3769 Oil lock free

I’m not pulling the rebound just yet, as you need to free the compression first. Push the comp stack in a bit, to reveal circlip. Remove valve.
IMG_3764

Easier said than done. My left leg came out easy enough, by putting a 15mm wrench between the valve, and treading in the adjuster, then tapping it with a rubber mallet
A little help

It wasn’t so easy on the right leg. Luckily I removed the oil lock 1st, then simply used the rebound valve to tap out the compression valve. Here’s the compression valve freed!! IMG_3774
Here we go
Compression Valve

Mr.S gave me a suggested comp and rebound stack that would work for me. I went with a .75kg spring. Note, Race tech spring is 35mm longer than the OEM. I’ll need to cut the spacer back. White end, re drill holes for compression tool to go into.
IMG_3777 IMG_3778

You may need to order new shims to get the desired stack. I ordered mine from Rod at RMR in Vancouver. Good dude.

Pay particular attention to how the stack comes apart.  Lay it all out.  Take your time.  Don’t drink beer just yet.  Make sure that all shims go back on.  I forgot to put the .4mm last shim on my compression stack…I’ll be going back in shortly to install it.  OCD…
Here’s both OEM shim stacks
Comp and rebound valving

Here’s my shim stack, with a .75kg spring.  This will vary from rider to rider, and it’s not meant to be a go by.  You will need to figure out what works for you.  But the general idea is that by increasing the initial shims, i.e the 17 x .10 to a thicker 17 x .15mm shim this will errrmm….make thing better..Again, I know nothing.  The formatting below is a bit f. up but it will give you a basic idea.

Refer to the above picture for actual stacks.  Picture is accurate off my right fork leg.

Rebound stack.  Left leg.  Single shim/Valve to nut Stock  Shim OD/shim thickness (.10mm) # of shims new rebound  shim OD/shim thickness (.10mm) # of shims
17 x .40mm 1
17 3 17 x .15mm 4
16 1 15 1
15 1 12 1
8 x .20mm 1 9 1
12 x .20mm 2
15 x .20mm 3
Compression stack (actual) Stock  Shim OD/shim thickness  (.10mm) # of shims new compression shim OD/shim thickness (.10mm) # of shims
17 5 17 7
16 2 16 2
15 1 15 1
14 1 14 1
13 1 13 1
12 1 12 1
11 1 11 1
10 1 10 1
9 1
8 x .20mm 1
11 x.40 mm 1

Tubes.  Both fork tubes were in good shape.  Oil had metal residue but mostly from the forks.  It’s way to early for the coating to start falling apart
Fork tube

At any rate, the fork bushing has too much play, and this may contribute to the slop/wear in the outer fork tube. Cut a 0.05mm shim 19mm by 135mm. Sand the edges down. Don’t sweat it too much, it sits behind the bushing Bushing shim
here’s the link to his video. His forks had about 13k km.

We’re ready to put it all back together.
Follow OEM manual for re-assembly, except for:

  • Run rebound 3.5 turns, then screw fork cap on to rod, seating gently.  At that point tighten the nut, and pre load adjuster
  • Set oil at 50mm from top, c/w spring, fork fully collapsed.  Each leg should take about 700ml.
  • Torque all components except bottom triples.  I have mine at 12Nm.
  • Torque mark all your bolts
The sag range is about 65mm to 73 mm.
Start with 1.5 turns out on rebound adjuster. This equal to about 6 clicks. Will find 1 turn out is likely the right spot.
Enjoy your new boingers!

 

MID JUNE UPDATE!!

I have a mere 1500km more since the re valve.  That said, the front end feels great.  The initial dive is gone, and the forks feel more progressive, through out the travel.  On big hit/air, I still have about 1″ left before the forks bottom completely.
A couple of updates.  My buddy Richard put me on to some Kawasaki seals.  He measured them up and everything. Pics/part # below. Bonus sprung scraper top lip, which Honda seal doesn’t have. Price wise, it cost $28 CDN for two K seals (no dust seals), and $80 for the H seals, including two dust seals.  I will be installing these before my September trip, or if my H seals keep acting up.
Kawasaki seals vs AT seal

At 5800km, my left seal shat the bed.  I managed to save it with a seal saver, but lost a bit of oil in the process.
Free lubrication

BTW..2018 H fork part number here: 51410-MKK-D01.
Tell your dealer you want a set!!

 

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Rear Drive shaft Seals replacement and Staintune pipe

Before I begin…usual disclaimer:  This is not a guide.  Use at your own risk.  I’m a spanner and tend to make mistakes.  That said, it all went well once the procedure and ‘special tools’ were sorted out. The Yamaha (aka: Y) repair manual is very important here.  Reference pages 4-104 through to 4-118.  Not all pages are relevant to the fix.  As I only had to sort out the two seals on the shaft, and didn’t have to do anything on the seals on the wheel side.

My blue 2012, has 35000 Km on it.  The riding splits up about 60% on road, 40% gravel/offroad, with some water crossing thrown in for a good measure.

I recently pulled the bike to BC for a vacation with my wife and giant brown dog log 🙂

How our dog travels

Two days into the vacation, I went for a ride with a friend of mine from SSI, he pointed out that my shaft drive was leaking.  Nice.  I didn’t bother to get on the internet and find things out, decided to wait the week and a half, and have a proper look at it when I got home.  Just to be on the safe side, I bought some gear oil for a top up.  The initial leak was very slow.  But after 3 tanks or so (1100km) the leak started to really get quite steady.

Bike back on trailer, tugged it home, and put it up on the bench.  I removed the rear wheel, took a few pictures of the shaft/swing arm, and the pumpking.  I originally mcgrubbered  the shaft with a ratcheting strap, which thankfully got replaced with a 12 inch c clamp, and a small block of wood.

The leak was definitely coming from one of the shaft seals (Page 4-104 Item 7, or Page 4-104 Item 13 (note, Y does not break these out, one is a simple o-ring that goes around the outside of the bearing retainer nut, the second is the seal that sits outside the coupling gear, and inside the bearing retainer nut-SPOILER ALERT! this seal was the culprit)

Once the final drive assembly (aka: FDA) is out, the drive shaft (aka: DS) has two snap rings (circlips).  one at the top of it, one towards the bottom, which holds the washer and shaft seal.  Now, being a numptee, I tugged on the DS, in the hopes of the seal letting go, and coming out.  It did not.  Then I proceeded to skip the instructions of the Y manual, and go directly to removing the bearing retainer nut (aka: BRN).  Book calls for a special tool (which I didn’t have, but had a flat blade screw driver, and a hammer.  You can fix anything with a hammer!)

As the book states the BRN is a reverse thread.  To remove it, go clock wise.  So I did.  I removed it as far as I could, but still had the DS and seal in place.  If you give the ds a proper yank, it will come out.  Set the spring aside, clean and inspect the components.  As spoiled previously, the DS seal was fine.  No leaks, but at this point needed to be replaced, since it was bastardized by me.

Looking inside FDA you can see the coupling gear (aka:CG) nut, and washer.  The CG has a punch spot that needs to be straightened out before removal.

Issue one.  Y manual calls for a special tool (CG holding tool).  The CG spins with the CG nut.  So you need to hold one to remove the other.  An internet search turned up…..nothing.  Either make one, or buy one from a guy in the UK for 250 pounds.  Nope, Yamahasupertenere.com (aka: YST) to the rescue.  Impact wrench, and a small c clamp around the CG for good measure.  Off it went.  Easy!

At this point the CG and bad seal were out.  Next issue: Parts.  I called around, and no one in Calgary stocked the parts.  4 weeks delivery from Japan.  YST to the rescue again.  Not only did two members come forward in offering the two seals needed (thanks again Bernie from Victoria), but I also managed to scoop up the last two full sets of seals, and o-rings in the US (cheapcycleparts.com)  They shipped out yesterday from the US and should be here by end of week.

What I was surprised by is how much surface rust the CG had on it.  I cleaned it up, and sent it off with Camshaft, and I 2.1.4 inch socket to get machined for my special tool (Note: this is after I had my light bulb moment, that with a proper tool, the job would be easier, and done right)

I cleaned all the parts up nice nice!!, and waited for the parts to show up from Bernie. I ended up reusing the o-ring on the outside of the BRN, and installing the new seal inside the BRN.  I used a socket of the proper ID to drive the new seal in.  That done, I greased the CG and o-ring, threaded it in (ccw!!!) by using the new tool.  Torqued to proper spec.

I then proceeded to install the CG carefully (remember it goes on the inside of the new seal.  Install the washer (the out writing facing, wait for it..facing out), install c-clamp around CG, break out the impact, and impact away.  Now the book calls for 108 LB, the impact gun got close to it..I think.

On to the SD, and related seal.  The SD seal will need two different diameter drivers to get installed (one for the SD, one for the CG).  Slide the seal on, and washer over it.  I found a suitable bearing race that I had kicking around, and a socket (size escapes me right now), and drove the seal on to the SD.  Once that’s done, the seal and SD needs to be installed into the CG (don’t forget the spring!).   For this driver I used my left over staintune pipe.  Right diameter, and proper weight.  Worked like a charm.  Snap rings on, shaft back in swing arm, install wheel caliper, associated bits, bolt/torque wheel (90 ft-lb  If memory serves) do up FDA nuts, check all bolts/nuts, fill with oil, go for a drive, and listen for loud clunks 🙂

My breather did leak out a bit of oil (probably because the FDA was on its side/upside down a few times), otherwise she’s bone dry.

I have a spare set of seals (and two o-rings now) Which I plan to use on an exchange basis with YST inmates as they need it.  I’ll send you my spare set, the inmate orders a new one, and sends  those back to me.

Re-assembly was straight forward.  Mainly because I figured out how it all goes back together, the special tool made up by Camshaft’s son for the BRN.

Granted the impact and c clamp are a bit bush league, but they work.  Pretty sure the dealers go the same route.

I have a suspicion that this will become a maintenance item.  If you ride offroad, gravel, streams etc..the grime and gunk collects at the bottom of the shaft drive, and since the BRN is stationary, the seal that sits between it, and the CG seal will eventually let go.

So to sum up.  You will need a proper BRN tool machined or made up.  It will make life easy, and get the proper torque to hold the bearing in.  The seal drivers can be sorted out easily enough with different socket sizes.  The CG nut can come on and off with an impact gun, the c-clamp helps a bit.  I expect to do this again in about 35 thousand KM.

Update October 2015.  I’m at 69 thousand km.  No signs of leaks.  The culprit was the swing arm plug, and nothing else.  Check your plugs gentlemen!

link to parts page: http://www.yamahapartspro.com/oemparts/a/yam/5004d842f87002275461de7b/drive-shaft

And the parts that you may or may not need:

Number #14 on parts page: 93102-50009-oil seal for main shaft. This will only give you trouble if the plug falls out…
Number #39 on parts page: 93108-49003-00 only needed if you’re not ginger with the original seal
Number # on parts page: 93210-69628-00 O ring for retainer bearing. Can reuse old if needed
Number #21 93211-54698-00 Inner O ring

Pics below:

Before disassembly
FDA wheel side
It eventually came off.... My special tools, c-clamp, and impact gun. Done. SD and spring. the Y manual, a must! Special Y tools needed. FDA ready for dis assembly Spot the leak
The bits! BRN and Seal BRN My 'clean' work space SD and new seal SD seal driver (outer) to go into the CG Proper way to hold the FDA.

Staintune pipe fitting

I’m on my second aftermarket pipe.  The first one was an early purchase in 2011 when I first got the bike.  Brand was ART.  Left a bit to be desired.  Cut my losses and sold it to my buddy Wade.

Next up was my two brothers.  Decent pipe, but a bit loud for my taste, and needs repacking.

Having previously ran Staintunes  on my DL1000, I followed Dave6’s lead, and purchased a second-hand pipe.  Cut it up, trial fitted, and sent it off to Dave6 for welding.

The Staintune was from a Triumph 955.  I used part of the stock pipe (clamp, and part of the pipe), the rest was from the staintune.  I wanted the new pipe to clear the rear of the bike, and exhaust straight out, not down, where it would melt my Givi bag (thank you ART pipe), or one of the turn signals, or fender (again, thanks ART)

After trial fitting the pipe, turn signal, and racks, the pieces were marked up, and left with Dave.

I had to get some aftermarket turn signals (ebay cheapies from china).

Result.  I’m very happy with the pipe.  It’s lighter than the two brothers, will never need to be repacked.  With the baffle out, it sounds great.  With the baffle in, it has a very nice note, but it’s not loud at all, and will do nicely on longer trips.