Planet Minis

arlindsay1992 · 08-20-2006, 06:41 PM

As the title says, I bolted on the CRF50 top end. So now I have a ZRF50. Anyway the install was easy and quick. Maybe an hour and a half. The hardest part was getting the exhaust back on. I think I may be bent a little because the heat shield gets in the way of the bolt that go to the head and I had to dremel out a bit of my frame to get the mount next to the airbox to fit. Anyway I got it. I used the same cylinder, just honed it again with my ball end hone. Not the cheap windshield wiper looking things. I made a time lapse movie but I'm working on editing it so right now it's just a folder with 492 pictures. Anyway, it sound a bit like a diesel. (pinging or claniking kind of sound. I don't think anything is wrong just different. Correct me you guys think otherwise. I'll get a video of the bike up in a while also. I got all new gaskets everywhere. The power is most noticable under acceleration. A couple of weelies were *accidentally* pulled starting out at traffic lights. I can now get up hills in third gear at low revs. I like it a lot. It revs through the gears faster but my dad won't let me get taller gearing so that sucks. The valves wer adjusted with a Safeway Select soda can so later this week I'll stop by my grandad's house and get feeler gauges and the compression tester. I'm going to do some carburetor tuning tomorrow and try taking out the choke again. Maybe I'll get it to work right with the new cam and top end. If you need pictures just wait for the time lapse. Then you can stop it wherever you want. If you want specifics, ask I can take pictures of the outside of the new top end but any pictures of my old head and piston.

88cc50 · 08-20-2006, 06:53 PM

Its probably sounds like its rattling because the rocker arms aren't adjusted correctly. you definately need a feeler gauge to check them right

arlindsay1992 · 08-20-2006, 06:55 PM

I know. But I really wanted to get it together so I used someone suggestion for the soda can.

kane · 08-20-2006, 09:20 PM

it shouldn't sound like a diesel, it should sound like your bike originally did with the older set up. So you set the valves using a piece of aluminum can as your make shift feeler guage? That sounds like a good idea and should get you pretty close. Are you sure you put that piston with the intake side pointing up?

Kurlon · 08-20-2006, 09:24 PM

Clay the piston and make sure you're not getting piston to valve contact, or piston to head contact. There shouldn't be any clinking/pinging noises.

C_Thut · 08-20-2006, 10:04 PM

when i get back to my dads ill check a soda can with my micrometer, how much play should there really be?

kane · 08-21-2006, 05:05 AM

you set the valves @ .002-.003" at tdc. If you feel the valves at they're tight rotate the crank ccw(counterclockwise) 360 back to tdc. Then adjust the valves.

arlindsay1992 · 08-21-2006, 06:35 AM

I know that the valves were adjusted the valves were adjusted with the exception of the aluminum can part. I konw the piston was installed correctly. I know that the exhaust isn't leaking because I pried out the ould gasket and put in a new one. I think it's just the valve adjustment. I'll get it fixed as soon as I get the feeler gauges.

Kurlon · 08-21-2006, 06:54 AM

Please please PLEASE clay the piston before you go too far. : ) Especially on smaller bore, stock piston motors, the valve reliefs are often too shallow for crazy lift cams. You also need to make sure the valves aren't touching EACH OTHER during operation, which can happen with too much overlap for the head design.

I'm assuming you're running the 'TBQ' cam and not something real wild like the Z40 grind, so valve to valve should be OK, but it's always good to verify.

arlindsay1992 · 08-21-2006, 06:59 AM

I have this cam. He says it will work with stock CRF50s and I have the equivelant of a CRF50 top end so I don't really feel like pulling the head off all over again to check. It doesn't really sound like metal tapping but like something else hard to explain. I'll get a video soon.

http://dragonracingparts.com/tbqracecam.html

kane · 08-21-2006, 08:01 AM

does it only make that sound when you first take off when the motor has been sitting?

arlindsay1992 · 08-21-2006, 08:23 AM

It happens a bit louder whn the engine is cold, yes. Bu it still happens when the engine is warm.

kane · 08-21-2006, 10:09 AM

did you check the cam sproket is lined up with the notch on the head at tdc?

Kurlon · 08-21-2006, 10:26 AM

When Dr ATV talks about head compatibility, he's only referring to valve on valve contact, NOT piston to valve contact, which you could be having. Pop the top end, it doesn't take long, and makes me sleep better at night. : )

arlindsay1992 · 08-21-2006, 10:43 AM

The cam timing is perfect. I spent a good five minutes checking and double checking. About the sounds, I REALLY don't want to take off the head again. It's a hastle. I also noticed that it sounded almost exactly the same as my 1988 Z50R. It must have something to do with the new style head or something. But I am not planning on taking it apart... now. But if I get bored one day. I'll check. Is there a special type of clay to use? And how do I clean up the clay from the internals?

Kurlon · 08-21-2006, 10:58 AM

I just use play-doh. Put a ridge across the piston, starting at the top, across the valve reliefs, to the bottom. Doesn't have to be much, a pencil width ridge is plenty. Bolt up the top end, torque it down, set the cam timing, and turn it over 3 or 4 times by hand. Remove the top end, and look at the clay. The thinnest portion should be at least .030" thick.

As far as clean up, the play-doh just pulls right off in one piece, I've not had any issues getting it all out.

arlindsay1992 · 08-21-2006, 11:01 AM

I'll try it someday.

fatcaaat · 08-21-2006, 11:11 AM

Try adjusting the cam chain slop. It was probably time to replace that cam chain anyway. Pop the 14mm nut under the engine (lay the bike on its side first). Remove the stator plate and make sure there is not too much slop in the chain. That makes an interesting noise when loose.

arlindsay1992 · 08-21-2006, 05:23 PM

It didn't make the sound before the rebuild. But I've never adjusted it so I will tomorrow. It's late here so I can't really. But it's probably time.

arlindsay1992 · 08-21-2006, 07:26 PM

Here's the movie. I can e-mail a larger hi-res version if anyone wants it (17megs). It's too big for Photobucket. The hi-res version has no weird music, however.

08-20-2006, 06:41 PM	#1 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Got the CRF50 top end installed with the DrATV race cam As the title says, I bolted on the CRF50 top end. So now I have a ZRF50. Anyway the install was easy and quick. Maybe an hour and a half. The hardest part was getting the exhaust back on. I think I may be bent a little because the heat shield gets in the way of the bolt that go to the head and I had to dremel out a bit of my frame to get the mount next to the airbox to fit. Anyway I got it. I used the same cylinder, just honed it again with my ball end hone. Not the cheap windshield wiper looking things. I made a time lapse movie but I'm working on editing it so right now it's just a folder with 492 pictures. Anyway, it sound a bit like a diesel. (pinging or claniking kind of sound. I don't think anything is wrong just different. Correct me you guys think otherwise. I'll get a video of the bike up in a while also. I got all new gaskets everywhere. The power is most noticable under acceleration. A couple of weelies were accidentally pulled starting out at traffic lights. I can now get up hills in third gear at low revs. I like it a lot. It revs through the gears faster but my dad won't let me get taller gearing so that sucks. The valves wer adjusted with a Safeway Select soda can so later this week I'll stop by my grandad's house and get feeler gauges and the compression tester. I'm going to do some carburetor tuning tomorrow and try taking out the choke again. Maybe I'll get it to work right with the new cam and top end. If you need pictures just wait for the time lapse. Then you can stop it wherever you want. If you want specifics, ask I can take pictures of the outside of the new top end but any pictures of my old head and piston.

08-20-2006, 06:53 PM	#2 (permalink)
88cc50 PM Newbie Join Date: Jun 2006 Location: Rochester, New york Posts: 72	Its probably sounds like its rattling because the rocker arms aren't adjusted correctly. you definately need a feeler gauge to check them right

08-20-2006, 06:55 PM	#3 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	I know. But I really wanted to get it together so I used someone suggestion for the soda can.

08-20-2006, 09:20 PM	#4 (permalink)
kane 2nd Gear Member Join Date: May 2006 Location: murrieta ca Posts: 717	it shouldn't sound like a diesel, it should sound like your bike originally did with the older set up. So you set the valves using a piece of aluminum can as your make shift feeler guage? That sounds like a good idea and should get you pretty close. Are you sure you put that piston with the intake side pointing up?

08-20-2006, 09:24 PM	#5 (permalink)
Kurlon Super Moderator Join Date: Feb 2005 Location: Windham, ME Posts: 8,303	Clay the piston and make sure you're not getting piston to valve contact, or piston to head contact. There shouldn't be any clinking/pinging noises.

08-20-2006, 10:04 PM	#6 (permalink)
C_Thut 2nd Gear Member Join Date: Jun 2006 Location: morris/wolcott CT Posts: 322	when i get back to my dads ill check a soda can with my micrometer, how much play should there really be?

08-21-2006, 05:05 AM	#7 (permalink)
kane 2nd Gear Member Join Date: May 2006 Location: murrieta ca Posts: 717	you set the valves @ .002-.003" at tdc. If you feel the valves at they're tight rotate the crank ccw(counterclockwise) 360 back to tdc. Then adjust the valves.

08-21-2006, 06:35 AM	#8 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	I know that the valves were adjusted the valves were adjusted with the exception of the aluminum can part. I konw the piston was installed correctly. I know that the exhaust isn't leaking because I pried out the ould gasket and put in a new one. I think it's just the valve adjustment. I'll get it fixed as soon as I get the feeler gauges.

08-21-2006, 06:54 AM	#9 (permalink)
Kurlon Super Moderator Join Date: Feb 2005 Location: Windham, ME Posts: 8,303	Please please PLEASE clay the piston before you go too far. : ) Especially on smaller bore, stock piston motors, the valve reliefs are often too shallow for crazy lift cams. You also need to make sure the valves aren't touching EACH OTHER during operation, which can happen with too much overlap for the head design. I'm assuming you're running the 'TBQ' cam and not something real wild like the Z40 grind, so valve to valve should be OK, but it's always good to verify.

08-21-2006, 06:59 AM	#10 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	I have this cam. He says it will work with stock CRF50s and I have the equivelant of a CRF50 top end so I don't really feel like pulling the head off all over again to check. It doesn't really sound like metal tapping but like something else hard to explain. I'll get a video soon. http://dragonracingparts.com/tbqracecam.html

08-21-2006, 08:01 AM	#11 (permalink)
kane 2nd Gear Member Join Date: May 2006 Location: murrieta ca Posts: 717	does it only make that sound when you first take off when the motor has been sitting?

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08-21-2006, 08:23 AM	#12 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	It happens a bit louder whn the engine is cold, yes. Bu it still happens when the engine is warm.

08-21-2006, 10:09 AM	#13 (permalink)
kane 2nd Gear Member Join Date: May 2006 Location: murrieta ca Posts: 717	did you check the cam sproket is lined up with the notch on the head at tdc?

08-21-2006, 10:26 AM	#14 (permalink)
Kurlon Super Moderator Join Date: Feb 2005 Location: Windham, ME Posts: 8,303	When Dr ATV talks about head compatibility, he's only referring to valve on valve contact, NOT piston to valve contact, which you could be having. Pop the top end, it doesn't take long, and makes me sleep better at night. : )

08-21-2006, 10:43 AM	#15 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	The cam timing is perfect. I spent a good five minutes checking and double checking. About the sounds, I REALLY don't want to take off the head again. It's a hastle. I also noticed that it sounded almost exactly the same as my 1988 Z50R. It must have something to do with the new style head or something. But I am not planning on taking it apart... now. But if I get bored one day. I'll check. Is there a special type of clay to use? And how do I clean up the clay from the internals?

08-21-2006, 10:58 AM	#16 (permalink)
Kurlon Super Moderator Join Date: Feb 2005 Location: Windham, ME Posts: 8,303	I just use play-doh. Put a ridge across the piston, starting at the top, across the valve reliefs, to the bottom. Doesn't have to be much, a pencil width ridge is plenty. Bolt up the top end, torque it down, set the cam timing, and turn it over 3 or 4 times by hand. Remove the top end, and look at the clay. The thinnest portion should be at least .030" thick. As far as clean up, the play-doh just pulls right off in one piece, I've not had any issues getting it all out.

08-21-2006, 11:01 AM	#17 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	I'll try it someday.

08-21-2006, 11:11 AM	#18 (permalink)
fatcaaat 3rd Gear Member Join Date: Sep 2004 Location: Arlington, VA Posts: 3,780	Try adjusting the cam chain slop. It was probably time to replace that cam chain anyway. Pop the 14mm nut under the engine (lay the bike on its side first). Remove the stator plate and make sure there is not too much slop in the chain. That makes an interesting noise when loose.

08-21-2006, 05:23 PM	#19 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	It didn't make the sound before the rebuild. But I've never adjusted it so I will tomorrow. It's late here so I can't really. But it's probably time.

08-21-2006, 07:26 PM	#20 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Here's the movie. I can e-mail a larger hi-res version if anyone wants it (17megs). It's too big for Photobucket. The hi-res version has no weird music, however.