KTM 640 Adventure Rally Build

[WesleyDRZ400]

Well might as well start a build blog,

The build is based on a 1997 KTM 620 Adventure EGS

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The plan is to have it abit like this...………………….but better

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Current Progress

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[WesleyDRZ400]

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[gothbiker]

Looking good, are you building the sump guard yourself


Sent from my iPhone using Tapatalk

[WesleyDRZ400]

Looking good, are you building the sump guard yourself


Sent from my iPhone using Tapatalk

Probably adapt the current one which has right hand side cut off for the low exhaust, as this bike is the 620 EGS Adventure model it came with the low exhaust and sump guard with the side missing, I have a tool box I will fit on the front and maybe a left hand side compartment

[WesleyDRZ400]

Might as well start with the engine.

So In 2015 brought this bike cheap and was about to go do Spain/Portugal route and went to my friends with plans to get the evening ferry to Spain.

Oil looked clean when I brought it and recently had service I was told, did the novice mistake of not doing a oil change myself on this new old bike

As many of you are aware you can find problems like cross threaded drain plug or threads missing ect ect

Well when I drained it I found metal, lots of what looked like large bearing casing so engine was possible about to shit itself .

Trip canceled and decided to get engine stripped/rebuilt, around 2015 i was considering/planning on doing a South America trip in 2016/17 so thought might as well take this bike as new engine rebuild.

Started speaking to a guy with loads of knowledge and this happened

Hi Wesley, well since the bike is now 18yrs old and you probably don't have a full service history then its safest to assume that nothing has been replaced recently.
This means you should replace all the seals including and especially the valve guide oil seals as these will have gone hard and will start leaking. Personally i would replace all the bearings, particularly since you should upgrade the mains anyway to the latest skf explorer series ( nj306c3 and nj207ecpc3) and the gearbox intermediate bearing(the one behind the clutch) to the roller race bearing from the rallye model(58533025000). Fyi all the bearings can be sourced from a bearing supplier except the one for the gearbox intermediate shaft as this is a ktm specific part.When you get the silicone 'o'ring for the output shaft spacer (behind the sprocket 0770250021), buy a handful of these as these are often damaged when replacing sprockets, this then causes a leak which people assume is the seal but isn't. Because yours is the earlier model your sprocket is retained with a bolt and diaphragm spring washer (59033034044). This part number buys you both items for the price of the washer and the bolt comes pre locktighted, carry a spare! If you can spare the expense, i would recommend upgrading the clutch basket, primary gear and balancer to those from an 03-07 engine. These parts are a different primary drive ratio and speed up the input shaft and so reduce the torque loading on the clutch and so reduce the risk of slipping. Because of the high price of new parts these can be obtained 'used' via the usual channels. You may also wish to replace the bottom oil filter cover with one from a 2001 onwards model. This is because yours uses an 'o' ring which is a twat to fit and the later item uses a reusable gasket which is much easier to fit when changing filters.( gasket 58530041000). You must inspect the stator and rotor, first generation e start models ('96) were fitted with rotors with unshrouded magnets which came off and caused carnage! Make sure your rotor has shrouded magnets and inspect the stator for signs of any previous mishaps! I mention this because engines for early '97 bike were built in '96 and given its age there is always the chance that someone may have fitted a used item from a '96 model if there has been a reason to replace before. Check starter mech gears for damage as these can lose teeth if some potato head starts cranking on the throttle while the e start is engaged. Opening the throttle while starting a big single is likely to induce a backfire, the sudden reversal of engine rotation against the efforts of the starter will result in damage to the teeth and the sprag clutch. The sprag clutch i would replace if i were you. If the intermediate gears show signs of abuse you can replace with later model items('98 on) but as these are a slightly different ratio you must replace all.( again used is fine if in good condition). Use genuine gaskets, they're better quality than any aftermarket ones I've seen and often reusable which is good news if you have to make an impromptu repair. These items plus the others I've previously mentioned cover the bulk of it, oh and don't forget to replace the inlet rocker arm roller as they are prone to fail. Hope this helps and hasn't put you off. I know it sounds a bit bad but to fair it is 18yrs old so exercising diligence is the name of the game.




£1800 later I had a great engine...………. then shortly after I had my first child the "babynator" so south America trip canceled

Bike was left feeling sad in the corner of the garage, iv have probably done less than 100 miles since rebuild as I just ride it a few miles each month and turn it over weekly.

So plans changed and I started collecting bits to do this planned bike build...……. it took awhile. That's the engine

[chunky butt]

I'm in

[WesleyDRZ400]

The parts I needed to make this build

Rally side tanks, however a few builds like the bike I put a photo up only fitted the right side tank as the left side tank hits the shock adjuster, air box and diagonal subframe brace

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Standard 640 adventure shock

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Standard 640 airbox

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[WesleyDRZ400]

At the back of the airbox is battery and electrical items, ecu, rectifier ect ect

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So I managed to get a ktm 660 rear rally shock which has the remote reservoir as standard so it won't hit the left side tank

Like this but not this one

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[WesleyDRZ400]

I then got a 660 airbox, it's massive compared to the standard one. You loose the space for the battery and electrical items

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[WesleyDRZ400]

So needed the rally subframe.....

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No luck so found this photo of one online decided to build one

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