17' 250RR rad pressure after cooldown. Piston, head and ring pics...

[NW_drZ]

Decided to go ahead and replace the rings to see if that helps my issue with the radiators maintaining pressure days after a ride.  When i remove the cap, pressure hisses and coolant splashes out everywhere.  The bike has 17 hours on it for reference.  To me it looks like coolant is seeping past the inner ring.  The oil has been discolored in this area making it look like coolant has mixed with the oil.  Just wanted to share because i know others are experiencing this from what i have read.  Also curious what your guys opinions are.

 

[ohiodrz400sm]

What are the out-of-flat measurements of the head and cylinder? Also, what is the size of the o-ring and the depth of the groove? Are you torquing the head when you assemble it?

That's a brand new bike under warranty. Shouldn't you be making the dealer tear it down?

[NW_drZ]

3 minutes ago, ohiodrz400sm said:

What are the out-of-flat measurements of the head and cylinder? Also, what is the size of the o-ring and the depth of the groove? Are you torquing the head when you assemble it?

That's a brand new bike under warranty. Shouldn't you be making the dealer tear it down?

Not sure the answer to your questions.  And of course i plan to torque the head to specs like the manual says.  I ordered new rings and they were $7 dollars total.  I figured it was such an easy job I didn't want to make the trek to my dealer.  I have been talking to him about the issue and he offered to help.  He has been great with everything and always offers to do the work. For this job i didn't mind doing it.  Took me all of 10 minutes to pull this apart.  

[ohiodrz400sm]

I understand all that but I guess my point is perhaps there is a factory defect. If the seal groove is too deep there won't be sufficient compression on the O-ring to maintain the seal. If the mating surfaces of the head or cylinder are greater than the maximum allowable flatness tolerance you will also get leaks.

[silver_fox]

What's the deal with all the oil on the head? That should be dry.

[NW_drZ]

What's the deal with all the oil on the head? That should be dry.

Guessing that's from some of the oil in the gas, some of it not getting burned off.

Also noticed the security bolt felt under torqued compared to the rest. By a decent margin. Where most of the coolant built up with the oil is where the security bolt was on the head. Thinking that may have been part of the problem. I'll report back in this thread when I have the new rings in.

[Singletrack_rider]

Good grief. I think you need someone to come over and perform an exorcism on that bike to dispel it's demons. 

[NW_drZ]

11 minutes ago, GreenMT_Rider said:

Good grief. I think you need someone to come over and perform an exorcism on that bike to dispel it's demons. 

Haha.  Don in the Beta's defense most things have just been setup issues that I have had to work out.  Nothing with the actual bike, more with me.  There is no doubt this bike has been the hardest for me to adapt too comfort wise.  Its working much better now since I got the ergo's super comfy.  This is first actual issue I have had with the bike.  Unless we consider the excess clutch drag I had when I first got it ?

[Singletrack_rider]

Whether small issues or the setup new bikes can be a little frustrating. All you want to do ride the not fiddle with it. My first new ktm 2st was a test in patients. That 200 took me a while to figure out along with some mechanical problems.

 I know you will get it all sorted out.

[NW_drZ]

9 minutes ago, GreenMT_Rider said:

Whether small issues or the setup new bikes can be a little frustrating. All you want to do ride the not fiddle with it. My first new ktm 2st was a test in patients. That 200 took me a while to figure out along with some mechanical problems.

 I know you will get it all sorted out.

Don you still loving that 17 250xc?  and did you keep your 250F?

[Singletrack_rider]

Just now, NW_drZ said:

Don you still loving that 17 250xc?  and did you keep your 250F?

Yes sir, still loving it. Bike has 50+ hours on it now. It even had a malfunction. A screw backed out in the powervalve and jammed it up. Bike lost all its topend power. Was a head scratcher to figure out what happened. 

  Took the 250f out last Sunday for a ride , first time since picking up the 17. Forgot how nice the bike was . Both bikes have a very similar feel so it's an easy transition. No plans on selling the 250f. 

[Retromlc]

Have you got the ktm part numbers for tge I rings that fit the Beta 250 ?

[ohiodrz400sm]

Have you got the ktm part numbers for tge I rings that fit the Beta 250 ?

I've done a search and can't find the reason why KTM o-rings are recommended, only that they are?

What is the actual difference between the parts?

[NW_drZ]

Rings are in. Fired up the bike and road it around the street for a bit. No pressure in the rads an hour later after cool down. I'll be doing a true test hopefully tomorrow or Saturday in the woods. I'll report back with my findings.

Also thought id share this. KTm rad louvers on the beta. $5.50 each on RMATV. Much more sturdy and a nice tight fit. Don't shake around like the stockers did for me. Thicker plastic. KTm 4 stroke RFS 2003-2007

[BushPig]

17 hours ago, GreenMT_Rider said:

Yes sir, still loving it. Bike has 50+ hours on it now. It even had a malfunction. A screw backed out in the powervalve and jammed it up. Bike lost all its topend power. Was a head scratcher to figure out what happened. 

  Took the 250f out last Sunday for a ride , first time since picking up the 17. Forgot how nice the bike was . Both bikes have a very similar feel so it's an easy transition. No plans on selling the 250f. 

How you liking the 250xc in comparison to the 150s?

I have all but committed to a blue 250f for my next bike. But damn the new 250EXC looks good as well. Maybe TPI will prove good and be my next choice when its time to move on the WR.

[BushPig]

6 hours ago, NW_drZ said:

Rings are in. Fired up the bike and road it around the street for a bit. No pressure in the rads an hour later after cool down. I'll be doing a true test hopefully tomorrow or Saturday in the woods. I'll report back with my findings.

Also thought id share this. KTm rad louvers on the beta. $5.50 each on RMATV. Much more sturdy and a nice tight fit. Don't shake around like the stockers did for me. Thicker plastic. KTm 4 stroke RFS 2003-2007

Good to see a resolution to your issue.

[Goatse]

Good grief. I think you need someone to come over and perform an exorcism on that bike to dispel it's demons. 

It's the blue demons making him suffer for leaving Team Blue.

[BassMan]

Very nice looking cylinder wash, you sir are jetted very close. Love to see such a nice looking piston.

[NW_drZ]

1 hour ago, BassMan said:

Very nice looking cylinder wash, you sir are jetted very close. Love to see such a nice looking piston.

Thanks for that Bassman.  Im not super savy at reading a piston and jetting.  I actually haven't touched the jetting at all.  Completely stock, riding here in the PNW.

[NW_drZ]

2 hours ago, Goatse said:

 

It's the blue demons making him suffer for leaving Team Blue.

 

Ill always love Yamaha.. If they dropped a 6 speed, e start on the YZ250X id be all about that.  I do miss my FX at times, but when i jump on my buddies i do quickly notice how much easier the 250RR is to ride in the tight stuff.  Its that FX suspension that i miss so much :).