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Automatic de-compression fault 625 SXC

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I just changed camshaft to Sommer mitte/oben Rally camshaft and run in to this problem;

Automatic de-compression on Rally camshaft stopped working properly after ~200 km (130 miles)riding , it engages itself at too high rpm even over 1500 ~2000 rpm but it seems that when it should click ,when engine is running lower than 1200 rpm it does not click . It works as normal in start and when you turn engine over by hand , but it does click at normal idle speed and even 500 rpm over , what has gone wrong?? I definitely know how de-compression should work ,on normal cam it worked great but something has let down with new cam, all parts were new ,camshaft bolt was torqued to 35 nm and Loctite 243 screw locking was used on bolt threads.

What should i inspect when i take cam off once again!!

If you could point to right direction it would be great . :ride:

Thanks, Petteri :thumbsup:

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Sorry Petteri, I dont have a clue about your problem. But I would love to hear what you think of the cams once you sort out your problem. Did you loose any bottom end? How much do you think you gained? :thumbsup:

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Power gain was with not perfect carb settings really noticeable from 4500 rpm but effect might just be wrong carb settings ,here are what Sommer KTM suggested:For your configuration i would suggest the following jetting:

Needle OBEKR (the original) in 1. Position from top

better would be

Needle OBEKS in the 2. Position from top

Main jet 175 for cold conditions

Main jet 172 for warm conditions

Of course, you need to adjust the mixture.

I did not belive first that needle settings should be leaned ,so it was very rich and did not wake up properly ,i´m still on rich side and obviously i need to change idle jet from 48 - 45 .

I did some acceleration test with my friend -05 525 EXC /Full Akrapovic , 14/50 gearing , my bike has full Akrapovic,power blade,no snorkel ,open airbox cover, rally cam,15-44 gearing ,acceleration was tested on gravel road ,from rolling start ,1 -gear onwards to 80 mph , my bike was dead even with EXC and EXC started to drop at 75 mph because of short gearing !

I don´t know if EXC was slow or my bike fast , figure out yourself :ride:

I could have even leave EXC a bit if there wasn´t jump on road and had to close throttle for a while , sadly we haven´t compared bike when my bike had stock cam.

I tried EXC and was dissapointed a bit i waited totally mad experience because low weight but i think my bike felt a bit stronger /keener because power rush when carb settings cleared ~4500 rpm. :thumbsup:

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