I have been loosing compression and it sounds like I might have a broken valve? So I have been told as well. I had the stage 1 kit put in it a couple years ago and they forgot to up size the intake jets. I am being told that the problem is due to the engine running to lean and burnt a valve as well?

I am not having any problems starting it and the oil temp is normal. just got off the phone with a local dealer and they said to bring it in ($99.00) to diagnose the problem which could be anywhere from 1500.00 to 5000.00 if the motor needs to be rebuilt.

just a fyi, if you ever start thinking about buying a 1200 xl motor for your bike, forget it or if you come across one, buy it. they do not sell them anymore. They told me they rebuild the motors only and the 2008 or later makes are obsolete.

I have a 2004 sportster 1200XL (in the pic)

 

I think it's time to talk to someone else as your getting bad information.
If you have a "broken" valve the engine would not run at all (you may have burnt a valve but that's an easy fix), you can get a new motor from the factory (very expensive and would only be an option after a catastrophic failure).

 

thanks hotlap, I was going to asked that question as it is a concern of mine as well but I did not want to sway any comments.When I was talking with the dealer, actually to I was just getting the impression it is all about ...well "show me the money" and anyone can fix what is not broken.

 

For less than $1500 you can get all new HD screaming eagle heads,jugs and pistons.you won't need a new motor I'm sure.If you burnt a valve you could get your heads redone and pick up a few hp at the same time,or pick up a set of New HD heads,lots of options once you know whats really wrong.

 

I just pulled my spark plug and it looks OK. wouldn't it be scored or sooted up?

 

Just buy a compression tester.
Get the screw in type, pull the plugs, screw in the compression gauge, crank the motor over, repeat on the other cylinder.
Both should read very close.

You can have a bad valve, sometimes you need a new valve and a grind.
Sometimes just a grind will fix things up.

What makes you think you loose compression?
No way to tell that without doing the test, unless you have a kickstart...

A burnt valve stays burnt, and would always run poorly, and I don't think it would last long before it melts, breaks, and trashes the cylinder.

Brett

 

Brett001,

when I am riding it seems like I have to stay on it more to go the same speed usually 35-50mph) and I have to downshift to keep the motor at the same rpms. When I am doing more than that around 60-65, it seems to be at a very high rpm and the engine seems to be working harder than it should. I guess it would be easier to know if I installed the tach I bought last year still in the box.

 

If your willing to learn about what goes on with the engine once you hit the starter button, you really should get a factory service manual.

It will show the breakdown views of each system on the bike, from front to rear wheel. For 99$ you can get a service manual on ebay and a compression tester.

As for the problem of losing compression.... you say its easy to start? does it idle normally when warmed up? If so then its unlikely there is a valve burnt. As stated once a valve burns its done, that cyl will have little to no compression depending on severity of burn.

If its loosing it once hot.. normal temp after 5-10 miles, it could be a ring sticking or a tight valve guide that is holding the valve slighly open. If it is too lean from improper jetting I would bet one of these is going to be the problem.


Or it could be a timing sensor getting hot and failing retarding the timing maybe?? I have'nt had any problems w/ my 05 1200 got 11,000 something on it so far....and still counting

Had another thought also, could the rear brake be dragging causing loss of power. Does it seem too warm after a ride??

 

There are lots of things that can cause a power loss.
Mixture is one of them.

Brett

 

your second to the last comment about the timing sensor made me remember after I got it service about a month ago, I was riding it home and for about a mile I smelt something that smelt like a wire was burning. It made me remember back in 05 I had the starter cable replaced as it was burnt through and had to be replaced (under warranty than). anyway I pulled over but than it went away. did not think much of it and just thought it was something wearing off from the service call. about a week or two later is when I started having the problem. never checked the back tire but I did just put new tires on it as well, mezeler marathons me880s