ADVrider

Go Back   ADVrider > Bikes > Thumpers
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-27-2009, 12:23 PM   #1
Tseta OP
Lost
 
Tseta's Avatar
 
Joined: Nov 2008
Location: Finland
Oddometer: 669
2003 KTM 640 LC4 Adventure Rebuild (HOWDID)

Hello,

I briefly mentioned having acquired a new motorcycle in the generic KTM 640 Adventure owners, sign in please… thread. Per the request made in there, I am posting a more complete summary of the rebuild process my new-to-me motorcycle has gone through in the last few months.

Once again, I would like to take the opportunity to thank all of the forum members who have contributed with the various guides and how-to’s: without the collective wisdom of this board, my rebuild process wouldn’t have gone nearly as smoothly as it did.

Additionally, I realize this post doesn’t have nearly enough pictures of the various maintenance procedures. I greatly regret not taking more photos during the rebuild process, but when you’re “elbows deep” in grease and soot, photography is neither very convenient nor high on the priority list. However, all essential maintenance procedures are well documented in the indexed how-to-threads with plenty of clear pictures and concise instructions. So, without further ado…

The Bike

I bought the bike as a Christmas present for myself from a store nearly 500kms away. Truth be told, I had been eyeballing something similar for a while, and once I saw this individual pop up on the used bike listings, I immediately went and purchased it. My purchase decision was not hindered by the fact that the price was very reasonable.

This is what the bike looked like when I picked it up for the haul home:


I glanced over the bike while at the dealership, using the tips and pointers posted in this thread. Overall, the bike looked fairly “clean” and mechanically sound, at least as clean as one can expect for 18000kms. For instance, the front rim recall had already been performed and the air filter looked quite unsoiled. However, there were no service records available for the motorcycle, the valve cover was seeping some oil and the test ride showed that carburetion was not exactly “spot on”. I was not worried though as I had already been lurking around this forum for a while, reading (and re-reading) the threads in the LC4 index. I was fairly confident that the few issues would be nothing that a complete teardown wouldn’t fix. While the concept of tearing down a “new” (or pre-owned in this case), functioning bike probably sounds quite silly to some (“if it ain’t broke, don’t fix it”-mentality…), to me it comes naturally: I’ve been doing the very same thing for almost all mechanical things that I have owned. Besides, what better way to familiarize oneself with the bike and its inner workings than a complete teardown and reassembly?

The Rebuild

After hauling the bike home, I made a clear plan to work from the rear of the bike towards the front, cleaning, fixing, adjusting or replacing each part as I came across it. Once done, I would just reverse the disassembly process in the best Clymer/Haynes tradition (“installation is the reverse of removal”) and I could call it done. This plan panned out mostly quite well; there were only a few things I had to go back to after assembling everything back together. This was no big deal, as I needed the practice in removing the front fairing etc.

The Rear End

Here is a picture of the early phases of the rebuild, with the rear fairings etc. mostly removed:


And here, with the tank and fairing removed:


I vigorously washed and brushed the old, dried mud out of many of the plastic parts and treated them with an “armor-all” type protectant. On the muckiest engine and chassis (metal) parts, a combination of solvents and rags was used. It was quite obvious that the previous owner had not cleaned the bike very meticulously since the muck was several millimeters deep at worst. Additionally, many of the aluminum parts such as the bashplate and the swingarm had quite heavy oxidation/corrosion marks on them. Of course this type of wear and tear is to be expected with a dual sport bike.

I ended up completely disassembling the rear suspension, linkage and swingarm. This guide was a great help. The old grease was just that, a dark, inconsistent mess. After a thorough cleaning, the bearings all seemed fine. Some light polishing was found on the linkage bushings, but I didn’t feel that they needed replacing just yet. The uncaged swingarm pivot needle bearings caused some additional work when most of the needles were “flushed” loose on to the table with solvent. Assembling the tiny needles back into the bearings with grease required a certain, calm and determined approach. Additionally, I had to think twice about the spot where the dog bones attach to the frame, as it seemed that the connecting axle had somehow grown in length during the cleaning process. However, I quickly found out that the assembly is meant to “float” to allow for the shock absorber to self-center. The shock absorber itself was taken to the local KTM dealer for an oil change and a fresh charge of nitrogen. I also checked/cleaned/lubed the rear wheel bearings, the chain and sprockets, checked the rim and spokes and mounted a new rear tire in preparation for the riding season. Around this stage I also had the rear subframe completely off of the bike: some “developing” rust spots and such were sanded and repainted.

Intake and Engine Top End

Moving forward on the bike, I came upon the air cleaner and the notorious BST-40.

Using this and this guide, I gave the carburetor a good once-over and performed the usual mods: drilled the slide holes to 3mm, installed a 157.5 main jet and a 47.5 pilot fuel jet, lowered the needle clip to the 4th groove and set the float height to its correct level. I also installed a KTM Factory airbox cover, but left the airbox snorkel in place. The previous owner had not gotten rid of all the EPC crap:

I removed the offending tangle of hoses very rapidly, plugged the appropriate port and installed filtered breathers in the two other ports, according to this guide.

Next up was the engine top end.

The valve clearances were simple enough to adjust with the help of this guide. I found that the intake valves were slightly on the loose side. The exhaust side did not need any adjustment. What did surprise me, however, was the large amount of axial play on the exhaust side rocker arm assembly. I asked about it in this thread and got pointed to the Re-sealing the KTM LC4 rocker cover guide. I ended up killing two birds with one stone: I got the axial play corrected with a 0.5mm shim and resealed the rocker cover, which should end the slow oil leak I had observed at the dealership.

Here’s a picture of the valve train with the rocker cover removed:


And here, applying new sealant to the freshly cleaned and degreased sealing surface:


Additional maintenance work around the engine included flushing the coolant system and filling it with fresh fluid, going through most of the electrical connections and treating them with dielectric grease, checking the countershaft seal and axial play, checking the orientation and condition of hoses, cables and wire looms, checking the tightness of various bolts and nuts (Loctite 243 was religiously used on almost every removed fastener throughout the whole bike…) and generally cleaning the muck. Additionally, I installed some silicone hose on top of the header connecting springs, centerstand return springs, and the muffler connecting springs, like this:



The trick aftermarket exhausts come supplied with rubber covered springs to prevent metal fatigue and eventual failure of the spring caused by vibration. I am hoping that the silicone hose will have some vibration damping effect and at the same time be heat resistant enough to provide acceptable service life near the cylinder head and the muffler connection.

The Front End

The steering head bearings were in a pleasantly good condition: no rust and only minor polishing of the bearing races. This guide was used as support material, even though I was feeling quite confident about the whole procedure.

Here is a shot of the bearings halfway packed with fresh grease:


The front forks were a completely different story. I have previously worked with some front forks; installed RaceTech Cartridge emulators, changed fork seals etc. but based on everything I had read, the hefty WP USD cartridge forks just seemed somewhat intimidating. Once I had nearly memorized this, this and the factory service guide, I set to work. Much to my surprise, the whole process was less difficult than I had imagined. Additionally, the fork oil was amazingly clean in both fork legs. The rebound needle of the right fork leg was utterly and completely stuck, which called for a complete disassembly of the cartridge unit. I did it the “hard” way, by removing the screw sleeve from the cartridge tube (per the factory instructions) since I couldn’t really comprehend the alternative method at the time. The screw sleeve was easy to remove with the cartridge tube held tightly in a vice with special prismatic aluminum jaws:



Once I got to the rebound needle, I found a large amount of black gunk which took a lot of solvent and time to clean. Thankfully none of the components had actually corroded badly: the cleaning was enough to make the rebound needle “unstuck.”



Curiously, the left fork leg’s rebound needle was in immaculate condition (I just had to disassemble it as well, even though the “quick” test showed no reason to…).

My suspension set-up measurements show that I have 55.5mm of static sag and 80.0mm of dynamic sag on the front end with 14.4mm worth of preload spacers (stock?) and 17.5mm of static sag and 90mm of dynamic sag with 28.2mm of preload in the rear. I weigh about 95kg, the rear spring is a 70-260 and I have no idea what the front springs are (probably stock). It seems that the current set-up is at least close to correct?

The front wheel bearings were also checked and lubricated, the spokes checked and tightened and the rebuilt forks were aligned in the triple clamps.

Other tweaks

I performed a quite thorough brake service in both front and rear, including cleaning and lubricating the slide pins and their rubber boots as well as changing the brake fluid. Another excellent guide was used as support material for this procedure. The rear brake caliper carrier is a delightfully clever design compared for example to the likes in some streetbikes, where the caliper with the carrier will readily fall without the rear axle in place.

I also switched the stock dash-mounted power outlet to a marine quality cigarette lighter-sized socket, installed KTM handguards (should have come with the bike but apparently the previous owner had “misplaced” them), installed neoprene seal savers onto the front forks and modified the shift lever with a “break here” hole and an additional threaded hole. I’m also planning on installing the KTM luggage racks and perhaps making my own roadbook holder for a GPS. Other mods will (probably) have to wait until I get a few kilometers rolled onto the odometer.



I still have to change the oil and oil filters, do some final checks here and there and wash and wax the whole bike. Then it’ll be ready for the riding season. I am considering some studded/spiked tires to take a head start…



Regards,

Tseta

Tseta screwed with this post 01-27-2009 at 01:31 PM
Tseta is offline   Reply With Quote
Old 01-27-2009, 12:38 PM   #2
Seikkailu_R
Studly Adventurer
 
Seikkailu_R's Avatar
 
Joined: Jun 2007
Location: Piikkiö, Finland
Oddometer: 821
With studded tires its so much easier to wait summer




Regards, Jarno


Seikkailu_R is offline   Reply With Quote
Old 01-27-2009, 01:36 PM   #3
Gale B.T.
Beastly Adventurer
 
Joined: Jun 2005
Location: Pagosa Springs, CO.
Oddometer: 1,400
Surely IMPRESSED

Tseta and Jarno, having tried several times to take pics and load the same on this site, I am always impressed with you Finlanders and what an awesome job you do, CONGRATS!!

I rode an '78 R100RT across Germany, Poland, Russia , Finland, Norway, Sweden and back to Germany in summer of '91. Sorry I missed meeting and having time to talk bikes with riders like you.

Thanks for the post,

gale, pagosa springs, co
Gale B.T. is offline   Reply With Quote
Old 01-27-2009, 03:14 PM   #4
neumie
Gnarly Adventurer
 
neumie's Avatar
 
Joined: Feb 2006
Location: Grand Brapids, MN
Oddometer: 127
Thanks

Thanks for the effort to put this together. I'll be checking valve clearances and steering head bearings this spring, and based on your description, probably a look at the forks.

Also, enough thanks can't be given for those who produced the guides Tseta listed!
__________________
2009 KTM 400 XC-W
neumie is offline   Reply With Quote
Old 01-27-2009, 09:53 PM   #5
meat popsicle
Ignostic
 
meat popsicle's Avatar
 
Joined: Feb 2004
Location: Circumlocution Office of Little Dorrit
Oddometer: 14,130
You're a good sport Tseta. And after thoroughly enjoying your well thought out and well written HOWDID I do not feel much guilt for teasing you so ambiguously in the sign-in thread... maybe I should do that more often!

I should add that your work on your new (to you) bike is an example to us all. The only bike that probably shouldn't need a tear-down would be creeper's ex-640, but as you said - what better way to get to know your new ride. Excellent job linking your resources, so that others can more easily follow in your footsteps. I'll make sure your HOWDID makes it into the index with an upcoming update (only 15 pages of subscriptions to ween... ).

__________________
Kronreif Trunkenpolz Mattighofen LC4 640

Its not so much staying alive; its staying human that counts.
meat popsicle is offline   Reply With Quote
Old 01-28-2009, 06:13 AM   #6
ChrisC
Molon Labe
 
ChrisC's Avatar
 
Joined: Feb 2003
Location: Prescott, Arizona USA Earth
Oddometer: 6,306
Quote:
Originally Posted by meat popsicle
(only 15 pages of subscriptions to ween... ).
+1 to Tseta's write-up (and it's wean, you dolt. Ween is a lousy rock band).
__________________
Chris
'03 KTM Adventure 640
'43 BSA M20WD
ChrisC is offline   Reply With Quote
Old 01-28-2009, 07:48 AM   #7
gunnerbuck
Island Hopper
 
gunnerbuck's Avatar
 
Joined: Nov 2005
Location: N.V.I, B.C.
Oddometer: 3,682
Tsetsa has an interesting looking bearing on his camshaft end....


Any one else have one like this on their 640? I'm thinking this is not a stock item....
gunnerbuck is offline   Reply With Quote
Old 01-28-2009, 08:53 AM   #8
meat popsicle
Ignostic
 
meat popsicle's Avatar
 
Joined: Feb 2004
Location: Circumlocution Office of Little Dorrit
Oddometer: 14,130
Quote:
Originally Posted by ChrisC
+1 to Tseta's write-up (and it's wean, you dolt. Ween is a lousy rock band).
chocolate and cheese...

gunnerbuck, I haven't been that deep in my LC4. Only approaching 15,000 currently.

P.S. Nice float height tutorial HERE, not that Tseta needed it, but I needed a good stash spot.

meat popsicle screwed with this post 01-28-2009 at 09:54 PM
meat popsicle is offline   Reply With Quote
Old 01-28-2009, 09:15 AM   #9
Seikkailu_R
Studly Adventurer
 
Seikkailu_R's Avatar
 
Joined: Jun 2007
Location: Piikkiö, Finland
Oddometer: 821
Quote:
Originally Posted by gunnerbuck
Tsetsa has an interesting looking bearing on his camshaft end....

Any one else have one like this on their 640? I'm thinking this is not a stock item....
Its probably more common HK2012 bearing.
Original is BK2012, type with blind end.

Maybe little less axial movement on camshaft with original type?
No aluminium / steel contact on cam end?
Or just for protect bearing from rocker cover sealant?
Seikkailu_R is offline   Reply With Quote
Old 01-28-2009, 09:40 AM   #10
Tseta OP
Lost
 
Tseta's Avatar
 
Joined: Nov 2008
Location: Finland
Oddometer: 669
Thanks for all the comments.

The camshaft bearing observations and discussion is very interesting. The previous owner(s) had obviously done some work under the valve rocker cover. He didn't do a very good job with resealing the cover (and especially cleaning the old sealant off), though: there was gray and black old silicone sealant on the sealing surfaces when I pulled the cover. I will have to check up on the engine top end, including camshaft, bearings and rocker arms during the next scheduled maintenance. Hopefully everything will hold up.

Edit: A quick Google search with Jarno's part numbers turned up the following bearings and their specifications:

BK2012, with a blind end
&
HK2012, with an open end.

The dimensions (except mass, of course), limiting speeds, load factors etc. are identical for both bearings.

Cheers,

Tseta

Tseta screwed with this post 01-28-2009 at 09:48 AM
Tseta is offline   Reply With Quote
Old 03-02-2009, 11:38 AM   #11
Tseta OP
Lost
 
Tseta's Avatar
 
Joined: Nov 2008
Location: Finland
Oddometer: 669
Quote:
Originally Posted by Tseta
...Other mods will (probably) have to wait until I get a few kilometers rolled onto the odometer. I still have to change the oil and oil filters, do some final checks here and there and wash and wax the whole bike. ...
Hello,

I had some free time last week and continued my 640 Adventure rebuild. The oil and filters have now been changed using this guide as reference, which was the last actual maintenance related item on the rebuild checklist. Other things are mostly mods/"farkles".

Inspired mostly by this thread, I decided to try making some footpeg extensions. I started out with 30mmx3mm flat steel stock and notched a rough sawtooth pattern on to one edge with a bandsaw.



Then I bent the notched steel strips into their approximate hoop shapes by hand. (OK, I used a vise also...)



Next I prepped the old footpegs by sanding the paint away from the area where I was planning to attach the extensions on to. Then I welded the extension hoops onto the footpegs using a MIG-welder.



The welds were then cleaned and the footpegs were quickly sprayed with some corrosion inhibiting zinc spray, followed by a few coats of primer and paint. I am very happy with the results. The extensions were simple enough to make and offer substansially increased control surface area.

Another project was coming up with a simple pannier system. I had previously purchased the KTM pannier racks. Once again, some thread I read here on AdvRider gave me the proper inspiration. I mounted some Pelican clones with a length of aluminum angle and Adel clamps.



I also modified the cases slightly by adding integral locks to them. The cases themselves are quite small. Hopefully in the future I will be able to aquire some larger cases, maybe even the pricey aluminum Zegas.

As previously planned, I also made my own roadbook holder bracket, mainly for mounting a GPS unit. By bending and sawing some leftover tubing, I was able to come to shape that was adequate for my needs.









Then I simply welded a rear support onto the tube to stabilize the whole assembly.



A quick shot of primer and paint was all that was required to complete the homebrew roadbook holder bracket.

Hopefully I will be able to start the riding season soon, as I am running out of things to mod/tweak. (Up next: bar risers, tool tube, home made fork subtanks etc.???)

Cheers,

Tseta
Tseta is offline   Reply With Quote
Old 03-02-2009, 11:51 AM   #12
meat popsicle
Ignostic
 
meat popsicle's Avatar
 
Joined: Feb 2004
Location: Circumlocution Office of Little Dorrit
Oddometer: 14,130
rock on Tseta

here's to you getting to ride her soon

and if you happen to test those Adel clamps please let us know if they work as intended.
meat popsicle is offline   Reply With Quote
Old 04-12-2009, 12:13 PM   #13
Tseta OP
Lost
 
Tseta's Avatar
 
Joined: Nov 2008
Location: Finland
Oddometer: 669
Hello,

I’ve developed quite a habit of working on my KTM during the longer holidays. This Easter I had time to make some handlebar risers and fork subtanks. I thoroughly enjoyed reading this thread about making raising links, so the following will be written in the same style, including lots of pictures.

The KTM LC4 handlebar clamps are bolted on to the top triple clamp with rubber bushings mounted on aluminum spacers and 85mm long, grade 10.9, M10 low headed allen bolts (which is quite a tall order at the local fastener/hardware store). Regular allen headed bolts will not fit, they will interfere with the handlebar. So I first set out to find some replacement bolts in various lengths so I could figure out the best height increase while keeping the cable and hose clearances in mind. Quite typically, the correct bolts could not be found, so I bought some regular allen headed bolts (in grade 12.9) and shortened the heads in a lathe.



Next I tried out various height increases by making different size stacks out of some washers.



I figured that about 30mm of height increase would be a good compromise. I measured the stock aluminum spacers and made some drawings based on the measurements. I had some round aluminum stock which was just about the correct diameter. I could quite easily machine the spacers in the lathe.



First I cut the aluminum to length with a bandsaw.



Then I clamped the piece to the four jaw chuck of the lathe and used a dial indicator to center it in the chuck.



Next, I made a facing cut to make the end smooth and true.



Some measurements, just to check.





Then I machined the outer surface to correct diameter for the required length.





The next steps were to center drill the end and then use a larger drill to drill through the piece. The edge of the hole was also slightly deburred with a countersink tool.









Then I used a parting blade to make a groove on the surface. The purpose of this groove was to aid in machining the end of the riser to the correct diameter and length.



The end was turned to the correct diameter and length with the help of the groove.





The “halfway point” of machining, no more can be done before the piece is turned around. I decided to shorten the excess stock with the saw before clamping and centering the piece the other way around in the lathe.







All that was left to do was to make the piece the correct length and smooth out the end with a facing cut and use a boring bar to enlarge the hole on the end for the rubber bushing. Also, the edges were deburred with a file and some emery cloth.







Here is the new bar riser compared to the stock piece. Making the second new riser exactly like the first proved to be quite difficult as the lathe I was using is not highly accurate.





---

I read a lot about fork subtanks for the LC4 here at Advrider. Especially this thread was of great help. Zerodog’s subtanks look very nice and are relatively inexpensive. I wanted to tinker and make my own subtanks. I used some standard pneumatic fittings and valves. The actual air tanks were made of plumbing supplies. The mounting clamps were hand made from flat steel stock and I am especially happy about the way they turned out. I’ll let the pictures do the rest of the talking for the subtank project.



























---


Meat, you expressed some interest in the Adel clamp-method of attaching the panniers to the pannier racks. Here are a few more detailed shots of the method I have implemented:





---

It has been a long winter. The start of the riding season seemed to be very close already, but then we got much more snow. All the streets are covered in snow once again. I don’t know how much longer I will be able to wait. If anybody has any good ideas for mods/farkles that I could (should?) still do to my bike then please let me know.


Cheers,

Tseta
Tseta is offline   Reply With Quote
Old 04-12-2009, 01:34 PM   #14
gunnerbuck
Island Hopper
 
gunnerbuck's Avatar
 
Joined: Nov 2005
Location: N.V.I, B.C.
Oddometer: 3,682
Looks like you have all the tools of the trade in your shop and your pretty handy with them.....

For another project suggestion I would say to come up with some form of on board tool storage... I've seen some pretty cool looking skidplate/toolbox combos.... But looking at where your tank vent tube runs to maybe you already have a toolbox instead of a charcoal can in place...
gunnerbuck is offline   Reply With Quote
Old 04-12-2009, 10:13 PM   #15
meat popsicle
Ignostic
 
meat popsicle's Avatar
 
Joined: Feb 2004
Location: Circumlocution Office of Little Dorrit
Oddometer: 14,130
fantastic as usual Tseta, thanks for the shots of the hardbag mounting. I hope Loadedagain pops in here; he is a machinist and could probably give you some good feedback on your riser work.

If you are getting cabin fever from the snow and looking for another project, why not make yourself a set of Trelleborgs...
meat popsicle is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 09:58 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014