I need help w/ my 98 SRX700

[CRASHTESTER]

What exactly is the function of the power valve system? My buddy wants to remove the power valves and block it off, but I think it would be a mistake. I don't know anything about the sled other than what I have read on-line. It did run, but the center piston burned up, so we replaced that, all the rings and new gaskets. Now we barely get any compression in any of the cylinders at all. I baught the sled from an auction, hoping to ride it with my daughter this winter. On Dec. 8th Katlynn passed away from a severe asthma attack, she was 13. I told my wife that I am losing my mind and need a hobby to give me a reason to keep going, that is where my sled comes into play. If anyone can help I would greatly appreciate it

 

[ttpowersports]

1st thing you do is slap your buddy....just kidding... sorry for your loss, the powervalve help to make more power by using back pressure off the exhaust.... i put over 6800 km on a 98 dont mess with it . have someone check it over that knows the yamaha and you will have lots of trouble free miles..... do not go with a mongose big bore...... stay stock.... good luck .and happy trails..

Terry

What exactly is the function of the power valve system? My buddy wants to remove the power valves and block it off, but I think it would be a mistake. I don't know anything about the sled other than what I have read on-line. It did run, but the center piston burned up, so we replaced that, all the rings and new gaskets. Now we barely get any compression in any of the cylinders at all. I baught the sled from an auction, hoping to ride it with my daughter this winter. On Dec. 8th Katlynn passed away from a severe asthma attack, she was 13. I told my wife that I am losing my mind and need a hobby to give me a reason to keep going, that is where my sled comes into play. If anyone can help I would greatly appreciate it

 

[powder junkie]

Leave them on and workn. Buddy had same sled with bender pipes and can and sounded awsome and ripped! Drove the bag off it for 7000+ kms. Tuff sled

 

[J-Roc]

So sorry to hear about your loss. Thoughts and prayers to you and your family.

What exactly was done with regards to measuring/ machine work on the cylinders before it was reassembled?

 

[jpgmtech]

Oh man, condolences for your loss!!!

On the engine side, keep the power valves. They work as designed. Those engines can produce big, reliable power.

As for no compression on any hole, I would be looking at how the engine was put together first. If it had compression on the good cylinder before teardown, and now currently has no compression, it would seem likely that something is not put together properly.

 

[powderhoundbrr]

Oh man, I am so sorry for your loss......

AS for the sled I am thinking bad gasket somewhere if you don;t have compression in any of the cylinders. I would tear down and re-build with a new gasket set and maybe get a manual to make sure everything is going back together as per spec. As for the power valves they are an important component and you need them to run well.