desomg

[Casper96]

Ok did the desmog over the last couple weeks or so, used the freeze plug method. Took her out for a couple short small rides with in a week or so of it being done. Go out yesterday to try and ride her a good one(nothing better to do) make a drop off about 15 minutes from my house go to continue on my ride and about 10 minutes later. A horrendous sound coming from the area of my left foot. Thought bend something in the valve train but bike was running great still. In looking around the bike find that the freeze plug that was right next to my left foot blew out somewhere around 645 under hard acceleration.

so the question is how do I keep this from happening again?

[DFragn]

I used JB Weld to fill in flush after installing the plugs. Never had a problem in 3 years.

[Tundra]

Make sure the plug is inserted all the way into the block, so the edge of it is flush with the block. Did you tap in in with a socket and hammer? I could not imagine how one could come out, possibly that one was a different size?

[Tropic traveler]

Agree with Tundra.
Either the freeze plug you used was too small or you didn't sink it down deep enough. I sunk the plugs on both our Valks deep enough that they bottomed out. A good 3/8" between the top of the plug & the top of the passage. I put JB Weld on top of the plugs on Kim's bike but didn't use anything on top of the plugs on my Valk. That was 30,000 miles ago.... no problems at all.
Definetly use a small deep socket or dowel of some sort to drive the plug straight down to bottom.

[Casper96]

Yeah the two on the left side of the motor he didn't like. He said when he put them in he had a problem getting the front one to seat we replaced that one right away. This one everything was good, was riding got about 15 minutes in made a stop and when i was riding 10 minutes later i shifted to 3rd and gunned it a at about 80 I thought I bent valve train.

So then my second question was if we fill the holes with JBWeld when he puts this one is it should be good right? Sounds like it from the other post.

[Cattman]

My desmog was done 35000 miles ago and while headed to HotGlues's week before last, I blew out the same freeze plug.  ???
I stopped in 4 different parts stores in the Frankfort Ky area for a freeze plug and finally got a bolt that was close in size to thread a few turns into the hole.  I know it had been placed almost 1/2" below the surface as were the others when I installed it 4 years ago. It blew out on a  rapid acceleration to pass a slower moving dump truck  and sounded like I had broken a valve off! I have a replacement plug to put in and plan on putting the bolt back in too.   I don't like riding a bike that sounds like a JD 520.  

[Madmike]

Which style of plugs did you use... the tapered cup style or the concave disc style??

http://www.seastrom-mfg.com/Seastrom_Manufacturing_Catalog/ExpansionPlugs.htm

[Tropic traveler]

Tapered cup style.
Make sure whatever socket you use to drive them down has some "wiggle room" in the cup. Otherwise you will have a hard time extracting it after driving the cup plug down. Don't ask how I know this.
Also, I think you have to remove the engine guard to get a straight shot at the front holes.


 Leftover Desmog parts pile.

[Casper96]

Yes the ones we used were the tapered cup. and yes you have to remove the crash bar for the front. This was the left side rear of the motor. Funny part is it had to come up towards me but I never saw it go. He was picking up some more today hopefully she will be ready to ride when I get home tonight.