Weekend ride with Low Compression - Any further damage?

Ok so I need some opinions.  I have a 2009 KTM 250 XC-W (2 stroke), that I just bought and kitted out for our upcoming weekend riding in MI.  It starts, and runs, and feels really strong.  I did a compression test and I'm only getting about 108 PSI from the motor (yes I held the throttle open while doing it).  I know it's going to need a top end rebuild, gaskets, rings, etc based on the low PSI.

 

My question is, is it safe to put another 100 miles / 10 hours on this thing this weekend, or am I risking doing any more damage to the engine and possibly increasing the cost of my repairs?

 

Any help is appreciated.  Thank you!

Maby I depends on how you ride it you could blow up the rings in 10 hours

Go ahead and ride it.

You should be OK. It just depends on how loose the piston is now and how much slap you're getting. If you do a bunch of high RPM riding yoy could risk breaking a skirt off the piston. But if you're just casual trail riding I doubt that will happen.

It's up to you if you want to you can but it might blow up in the woods and not start from no compression and you might have to tow it back that's really the worst that can happen

Thanks for the responses so far!

 

As far as type of riding, we are going to ride what I would call "aggressive woods riding".  So about 50 miles a day for 2 days of fast pace trail riding at Tomahawk in MI.  I'm not super concerned if it dies on me on the trail and wont start, I can get it out of there and we are taking a backup bike if it only makes it through the first day.

 

I just want to make sure I'm not going to turn a $200 top end rebuild - gaskets/rings/etc into something a lot more expensive.  No chance of damaging the cylinder or anything else important by letting it go too long? 

 

Anyone want to take bets on whether or not it will make it through the weekend :)

Thanks for the responses so far!

 

As far as type of riding, we are going to ride what I would call "aggressive woods riding".  So about 50 miles a day for 2 days of fast pace trail riding at Tomahawk in MI.  I'm not super concerned if it dies on me on the trail and wont start, I can get it out of there and we are taking a backup bike if it only makes it through the first day.

 

I just want to make sure I'm not going to turn a $200 top end rebuild - gaskets/rings/etc into something a lot more expensive.  No chance of damaging the cylinder or anything else important by letting it go too long? 

 

Anyone want to take bets on whether or not it will make it through the weekend :)

I think it would make it through the weekend but if you break a piston skirt you'll at a minimum hae to replate the cylinder, could do MASSIVE damage as well, break a cylinder, set of cases, yeah it could happen. But honestly are you sure it's only 108psi? I wouldn't think it would even run, should have at least 175lbs. 

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Edited by JG-KTM

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