Installed new cam today, won't start now... (650R)


43 replies to this topic
  • Billahjack

Posted June 06, 2007 - 06:24 AM

#21

There is a link for a PDF of the Honda XR650R service manual. I would search for that within the forums (search function on maroon commands bar up top) or on the www.XR650R.us website. Within there, you will find the timing procedure. I have the manual at home that I E-bayed for $20.

FYI - I never disengaged the Timing Gear from the cam chain while performing my cam swaps. I unbolted it from the cam then used a wire to pull it upwards to keep the teeth engaged with the chain.

  • Supplicate

Posted June 06, 2007 - 12:36 PM

#22

I have that pdf'd manual printed out and in a three ring binder sitting right next to my torn down bike. I'll see if I can find the stuff in the manual. Hopefully I'll get it running this afternoon.

  • Billahjack

Posted June 07, 2007 - 11:54 AM

#23

Need to make sure that the timing gear flange is oriented correct on the cam splines and the timing gear is correct relative to crank orientation.

  • Old_Man_Time

Posted June 07, 2007 - 04:54 PM

#24

I may have missed it but did you say the plug is now wet when you pull it after trying to start it? If it is not wet the Edelbrock is the problem. The horizontal fuel valve can stick.

Also, you are using the timing marks on the flywheel right? If you are using those correctly you do not need paint marks on your timing chain.

  • Supplicate

Posted June 07, 2007 - 05:18 PM

#25

I may have missed it but did you say the plug is now wet when you pull it after trying to start it? If it is not wet the Edelbrock is the problem. The horizontal fuel valve can stick.

The plug is dry. But I had it running not three hours before I pulled the motor apart. I still need to open up the Edlebrock and clean it out, I've read your thread a couple times about it. I noticed some rust in weird spots on the QS and it kind of bugs me :thumbsup:

Also, you are using the timing marks on the flywheel right? If you are using those correctly you do not need paint marks on your timing chain.

yep, using timing marks. I've just learned from years and years of rebuilding and certifying oilfield pressure equipment that its better to over mark something then have it go together wrong and destroy parts.

Thats why this bugs me so much, I took three or four hours doing this project and marking everything, just don't see how it got all ****ed up.

Anyway, the biggest trouble I had was making sure it was on TDC by the flywheel marks. Any hints on that so when I completely redo it from scratch it will go easier?

  • Old_Man_Time

Posted June 07, 2007 - 06:03 PM

#26

With a dry plug there is no way it's getting fuel past the carb fuel valve. I know you don't want to do this but squirt some starting fluid into the carb through the air box and kick it over. If it fires, tear your carb out and polish the valve and valve casing.

I noticed that you are concerned about your compression reading. Don't be until you get the bike started and oil sealing the rings. You always getter a better reading from a warm motor. You could squirt a bit of oil in the plug hole and kick it over with the plug out to coat the rings. Then take a reading but I believe a warm motor still gives a truer reading.

  • Supplicate

Posted June 13, 2007 - 04:03 PM

#27

Opened it back up again, checked everything out took some pics. By looking at these pictures, what do you guys think? Looks like I might be one or two links too far back on my timing chain:

Posted Image
Posted Image
Posted Image

Going to put the OE carb back on it and see if I can get it to run with that, then see if I can't find a parts diagram somewhere of the QS and rip into it one of these days coming up.

  • Thumpmeister

Posted June 13, 2007 - 08:43 PM

#28

Okay, I think I see the problem...

The little line next to the EX should be parallel w/ the top of the head; it looks like its either one tooth on the chain off, or its one tooth on the cam off. The tooth on the cam being where the flange was pressed onto the spines of the cam.

However, that shouldn't prevent it from running. It might make a little more noise than usual, but it should be able to run.

There has to be simple answer to all this...

When you put the valve cover on, and pull the plug and valve check covers, are you able to run the motor through all four cycles, and see when the valves open and close?

Could your spark be 180* off? Meaning it ignites on the exhaust stroke instead of the compression? Just a thought...

If thats not it, then it has to be that its not getting fuel...

  • Billahjack

Posted June 14, 2007 - 09:14 AM

#29

As far as Supplicate's issue, I didn't realize that there was a carb swap at the same time. I can't see the pictures at work so I'll take a look when I get home.

It would be killing me too if I had my bike down for a while.

  • Supplicate

Posted June 14, 2007 - 10:10 AM

#30

As far as Supplicate's issue, I didn't realize that there was a carb swap at the same time. I can't see the pictures at work so I'll take a look when I get home.

It would be killing me too if I had my bike down for a while.

Nah, the carb swap is a year old. Was running fine with the Qucksilver. I just have the OEM carb still sitting on the shelf that I can slap in there and try with it since I -know- it will get fuel into the cylinder. Going to try a few different things tonight since the suspension for the 250 isn't back yet and I need to wrench on something :thumbsup:

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • rdahl

Posted June 14, 2007 - 02:17 PM

#31

okay this thread is driving me nuts! I can't stand it when somthing can't be figured out!!!

Kinda hard to tell from the pics but it looks like the Key Hole on the cam gear holder isn't lined up with the strike mark on the cam. Maybe 1 spline off? I'd check that before you do anything else.... GOOD LUCK!!

  • creeky

Posted June 14, 2007 - 03:15 PM

#32

The paint mark on the chain will be of no use if the cam chain dropped off the crank sprocket and moved a tooth or two.

  • Billahjack

Posted June 14, 2007 - 06:14 PM

#33

I just went through my manual and Stage 1 cam/Flange. It looks like you are at the correct timing for the flange on the cam. My flange only fits on the hotcam one way for a sliding fit. Any other rotation and it will have to be pressed on.

I agree that you may be off by 1 tooth on the chain to the cam. The marks are supposed to be level with the cylinder head.

  • Billahjack

Posted June 14, 2007 - 06:18 PM

#34

Okay, I think I see the problem...

The little line next to the EX should be parallel w/ the top of the head; it looks like its either one tooth on the chain off, or its one tooth on the cam off. The tooth on the cam being where the flange was pressed onto the spines of the cam.

However, that shouldn't prevent it from running. It might make a little more noise than usual, but it should be able to run.

There has to be simple answer to all this...

When you put the valve cover on, and pull the plug and valve check covers, are you able to run the motor through all four cycles, and see when the valves open and close?

Could your spark be 180* off? Meaning it ignites on the exhaust stroke instead of the compression? Just a thought...

If thats not it, then it has to be that its not getting fuel...


Interesting thought on the spark being off 180 degrees. I believe that all bikes using a stator system fire every revolution. They do not have means to selectively choose which stroke to fire on. This means that it would not matter for spark.

  • Thumpmeister

Posted June 14, 2007 - 07:14 PM

#35

Interesting thought on the spark being off 180 degrees. I believe that all bikes using a stator system fire every revolution. They do not have means to selectively choose which stroke to fire on. This means that it would not matter for spark.


Yeah, I think so too. I would think that the bike would fire on the compression and the exhaust stroke, since there isn't really a method for the ignition to fire ONLY on the compression stroke...

But, like I said, it was just a thought. Since he seems to have covered that the bike IS getting fuel, and that his cam timing is ON, the only other explanation to why it won't even sputter would be the spark.

  • Supplicate

Posted June 14, 2007 - 08:11 PM

#36

Yeah, I think so too. I would think that the bike would fire on the compression and the exhaust stroke, since there isn't really a method for the ignition to fire ONLY on the compression stroke...

But, like I said, it was just a thought. Since he seems to have covered that the bike IS getting fuel, and that his cam timing is ON, the only other explanation to why it won't even sputter would be the spark.

yeah, we'll see about the fuel (again) tomorrow. Wound up running down to Utah to visit some family and enjoy myself since work is being a PITA, but thats another story :thumbsup:

  • HawkGT

Posted June 14, 2007 - 08:40 PM

#37

Correcto on it being impossible to be exactly 180* out in this case. The spark does fire on each TDC--it's called a "lost spark" or "wasted spark". Seems like most ignition systems are like that these days. If memory serves there was an XR or two from yesteryear that located the pulse generator on the cam rather than the flywheel. In those cases you could be 180* off.

The cam gear timing mark looks pretty close to me. I'm guessing that if you move the cam gear one tooth you'll be equally "off" except in the other direction. I'd think that "off-ness" could easily be because of cam chain stretch. With the cam chain tensioner on the left side, any extra slack is going to be taken up by the tensioner on that side--rotaing the cam counterclockwise in the process. But I don't think the cam being that much off is going to keep it from running. I bet that small amount of cam retarding will just move the power up the RPM scale a tad (maybe an unoticable amount).

And yes, when you look at the valves when turning the engine over by hand you can see the valves opening and closeing.

  • Socal_rider

Posted June 15, 2007 - 07:57 AM

#38

Looks to me like you have the Crank, chain and cam sprocket all oriented correctly. I don't think I got my point across clearly in my earlier post, but your picture helps. See in your last picture that there is a full ring of holes in the cam sprocket? The hub can be bolted to any of those holes, and it changes everything. I will bet that this is the problem. The picture is not quite clear enough to tell, but try to look at the inside of the cam sprocket and see if there is a "sillouette" of where the hub was bolted to the sprocket previously. This is a critical step and there are no markings to help.

  • Old_Man_Time

Posted June 17, 2007 - 09:01 PM

#39

Any news on this problem yet? I am curious as to what actually is wrong. :thumbsup:

  • Supplicate

Posted June 18, 2007 - 04:03 AM

#40

Any news on this problem yet? I am curious as to what actually is wrong. :thumbsup:

no news yet, had to work all weekend (one of the benefits of working for family :thumbsup: ) but am at the office @ 6am today so I can quit at 3pm and start trying to get the pig started.

Will keep you guys updated as I figure things out.





Related Content

Forums
Photo

2015 XR650L Squeaking noise by Crayjay


Dirt Bike   Make / Model Specific   Honda   XR600/650
  • 3 replies
Reviews

Honda XR650L 2016 by Chris.GVS


Honda XR650L 2016
  • - - - - -
  • 0 reviews
Forums
Photo

DirttyPig 2005 Xr650l Prroject! by braapmebb1moretime


Dirt Bike   Make / Model Specific   Honda   XR600/650
  • 22 replies
Forums
Photo

Would a Young Scott Summers still be Competitive today on an XR600R? What would he ride to be competitive today? by Jayzonk


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  158 replies
Forums
Photo

Fell Off Trailer by usafxr


Dirt Bike   Make / Model Specific   Honda   XR600/650
  • Hot  43 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.