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Maybe some of you remember my last MX 250 Chesterfield Rebuild from last year, after that i was on fire and want a new Projekt

In Oktober 2022 i found a SX 360 from 1997 but it was to good for a Full Rebuild just did a Suspension Upgrade and a small refresh

After this i want more a 500cc , but it is nearly impossible to find also here in Europe, found one 1989 in Check Republik for 12.000€ but that was to much.
In June 2023 i get two big Collections of 250/350/500/550 Parts , ended up with 8 Engines 4 Chassis a big Disaster




Out of that Parts i make one 500 over the Summer, Bike is Running but with very low compression and less Power.
That 500 Engine ned a lot of Work with Cylinder Sleeve, Crank Rebuild, Clutch Basket is shot……
So for the Moment i decided to leave the 500 like it is an Start a 540/550 Projekt
Out of these Engine there is one very nice 1987 540/550 Engine in an excellenct Condition, according to previous Owner this was a spare Engine from a Dutch Sidecar Team sittting in a Garage unused for over 30 Years
Startet with Engine Work while i am searching for a Frame, it turns out that 3 from 4 Frames i collect was from the 250 , but the big Engine just fit to the 350/500 Frame
Found some important missing Parts that week.
A New Leftover NOS 500 Frame and Swingarm from 1988 , and an Aluminium Clutch Cover the Magnesium Part is badly Corroded
Engine fits the Frame, the Big Bore Projekt is ready to start
love it! these late '80's ktm's are some of my favorite all-time. looks like it's gonna turn out awesome based on your previous work
Some slow Progress on my 550 Rebuild Engine is already finished
Piston is Wiseco and Conrod is Samarin from Spain , i think the only Manufacturer to get That Parts
The Shop
Luxon 4-Post Bar Mounts
$189.95 - $239.95
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Some more Pictures from the Engine, for Comparison a 550-500-300 KTM Piston
Carburator is a Keihin PWK 41 Pro
On the Pictures the Custom Made Samarin Conrod from Spain
These Parts (Piston-Conrod - Zylinder)are the only difference from 550-500 and 350 KTM, the rest Gear Box , Engine Cases , Clutch is almost the same on the 565 and 555 so it’s possible to interchange many parts on These 565 and 555 Engines
Great build man!
They are real rocketships!
Wheels and Shock finished that Week , but it’s a Challenge to complete that bike.
A 1986 Engine, 1990 Frame , 1989 WP Fork, 1987 WP Shock and a 1988 Swingarm dont want to fit together
I always wonderd how much rwhp these ktm's pull are u gonna do a dyno run?
It’s hard to say how much HP this 540/550 KTM make , there are almost no Information to find about these Bikes .
The old Short Stroke 500 (85-88) make 62 HP the newer 500 (89-95) make 65 HP
That 550 has a portet Cylinder, Boyesen Rad Valve , JSV Pipe and the 41 Keihin, maybe it came close to 70 HP, but yes a Dyno run would be interesting
I am in need of a clutch cover and clutch basket for a 1990 ktm 540. Any help towards parts is appreciated. Thanks. Also I have a dyno port cone pipe for a 1990 ktm 540 if anyone is interested!
The Clutchcover and Basket you can get from Andre Horvarth's Enduroklassiker in Vienna/Austria
These are New Reproduction Parts
Did you have some Pictures of the Pipe ?
I would gladly take this pipe! I just recently acquired a 90 540 and was going to call DynoPort and see if they’d be able to make me one.
Excellent work!
Not sure why it won’t let me post a picture of it. I’m going to keep trying.
Pit Row
What happen to your Engine ?
Water Damage ?
It sat outside in the weather for about 2 months without the clutch cover on it is what the person I bought it from said.
I posted a pic below. Hmu with an offer and a location and we can get a price and shipping figured out!
Also the corrosion is from the coolant reacting to the magnesium cover. I heard it was a problem for these bikes if you left coolant in it for long periods of time. I don’t believe it is water damage.
I sent you a message! Let me know if you get it.😃
That was a big problem on these Ktm until 1993 or 1994 when they switch to aluminium cover
That was mine from the 1986 - 540/550 Engine ,it was completely corroded
Yup that’s what I heard. My clutch cover is in decent shape. Question. What’s a rebuild on one of these engines costin?
I spend around 1.500 € which is almost the same in USD only in the Engine
Piston, Conrod, Cylinder Plating and Honing, Gerabox and Crankshaft Bearings, Clutchcover and Plates, Seals and Gasket Kit and the Cases -Cylinder Vapor blasted
It looks like I will start this journey on my 91 I just picked up🤯
Hard to tell from that Picture, but it looks good ,seems to be a DXC 540 with the big Tank
Much better than mine was ,yours is in one Piece 👍
Is it running ,did you tried to start it ??
I have not tried starting it because I was made aware of a crack in the jug on the top mating surface and its missing quite a few things. But I’ll be getting it back and running here in the next year or so. Sourcing parts as we speak.
Do have the Con Rod details from Samarin
Also the Rod lengths. 500 short stroke to 550 if there are differences ?
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