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Discussion Starter #1
Hi All,

I have been a member for some time reading people's builds and getting some ideas for my build. I chose to go with the KTM 540 sxs BB kit and the 806 cam. I also want to get the head ported and a valve job. Thinking of sending the head to Thumperracing for their trail port but still have not decided.

I am going to attempt to do the work my self. My mechanical skills are good but not knowing what to look for is going to be my problem. If you guys can help me in that department that would be grate. I did buy the KTM Repair Manual to help me along the way but I sill have some questions. I also have been looking at the videos on youtube just to get an idea of what I will be getting my self into.

What will I be using the quad for you may ask. Mostly dunning, sand drags and trail riding. I don't have to be the fastest quad out their but I still want to give the big boys a run for their money:D.

The quad: 2008 525xc got it new.
Curent mods:
Engine stock
Carb Ranchero mods, bored to 41 emulsion tube & dual AP squirter done by Thumper, HRC needle.
Exhaust full Akrapovic
FCI intake
Thumper crankcase breather.
Quad was jeted and dynod by Garret at Fuel Customes.
 

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I did the Thumperracing 540 kit. Worked out great. No problems. I was tripped up by the rings because there are 3 in the box, but you don't use one of them. You have to gap them properly otherwise you will be in trouble. Let me know if you need help on how to gap them, instructions are included in the box.

You will need a cam chain breaker/press and new cam link. Make sure you have a bolt to hold TDC, that helps a lot. It's a fairly easy process if you don't rush it and take your time, ask questions as you go. Refer to the manual, however it doesn't tell you everything. Consider the MINO water pump from Thumper also, easy bolt on.

I'd love you see a new dyno sheet afterwards.'

Good luck.
 

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Discussion Starter #3 (Edited)
I did not get the Thumper 540 kit I went with the KTM 540 sxs kit. One of the questions I do have.... Do the rings need to be gaped since it is a factory kit? If they do need to be gaped what do I gap them too? The repair manual says 0.80mm or .0315in for compression ring and 1.00mm or 0.0394in for the Oil scraper ring. The KTM kit did not come with instructions.

I ordered the KTM chain tool and also got the KTM ring compressor tool for the 97mm piston.

The MINO pump was one of my first upgrades.

Once it is all done I will get it back on the dyno

Thanks for the help
 

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I never did check the rings on the 540 SXS kit that went on my dad's machine and haven't had an issue with it. Typically, the bigger the bore, the more ring gap to account for expansion of the longer ring. If you want' to check it I would just make sure that it has slightly more than what a stock 525 is supposed to have. The piston/ring type is the same on the 540 SXS kit as stock so expansion rates should be similar. Ring gap is going to be different for different ring materials too so don't use recommendations from an aftermarket piston company (for example CP uses 0.004" per inch of cylinder bore). The ring compressor is a good idea. The factory oil ring is sharp and hard to compress by hand. I cut my fingers tips up pretty good getting mine together.
 
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