I always thought that the intake valves go out of adjustment first because of the cooling effect of the air fuel mixture hitting them over and over. They cycle in temperature at lot more then the ex valves. Great video!
When I was doing the valve adjustment on my 2007 RFS I didn’t quite get the nut tight enough on the left intake side and it came off, motor started ticking then died. E start just ticked and kick start was not budging, took it home and took it apart the nut got stuck in the cam chain. Luckily I got alway with just having to buy a new chain and nuts. Great content
Thanks for the validation. I spent 20 minutes trying to get it to land on TDC, then I was thinking, why don’t I just roll the engine until the intakes are open and do the exhaust, and vise versa? Thanks man.
So does it really matter where it is in the stroke as long as the intakes are closed and I can move the rockers up and down? Can I adjust the intakes like that? My bike has no auto decomp
I am hoping a valve adjustment will get this big red pig to start. I’ve done the carburetor and it feels like it doesn’t have a lot of compression priming it. I have the mechanics manual, and the shims just concerned about doing it myself
Is it natural to have some kind of valve noise, a bit of chatter? My exhaust valve were very tight about 0.003 less than spec, I put then to spec and I noise a chattering noise which was a bit more pronounced than before. I tighten the exhaust to maybe 0.007, let the engine warm and it seemed to help. Thinking I may have not use a feel gauge correctly (not coming at the side ) or perhaps the auto decompression affected my reading? The owner before me also put a higher compression piston and racing cam. Does the valves need to be tighter if that’s the case?
@@llecki I am pretty sure it’s a 68 but I need to check. That’s the problem with a bike that just works and rarely needs anything. I just don’t do much to it other than change the oil.
@@highlandcycles that's the way man, i chipped off about 10 lbs of dirt on caked motor of a xr500r, rode it for 10 year hard, it still is fine. intakes on a xr650r i've rode for a couple years now, runs like a beast, starts good is a tight .005 and exhaust is a bit loose from just checking at the tdc way, which might of been a bit off? i just put it back together and just gonna run it. or go the short route not worrying about pinpointing a tdc mark.
Hey highland. Trying to adjust my intake valves, I think I set them too loose before and they started ticking. I got to TDC the previous time I did them, they seemed a little tight so I loosened them to where I could fit 0.15mm feeler in and had a little drag. They weren't ticking before. I didn't touch the exhaust valves only intake. Started it up and it was ticking. Do I need to tighten them? Do you have a better explanation of how I know I'm in the correct position to adjust the intakes only? The intake valves are up and I can move the rockers up and down slightly. Is this the correct position?
I should mention the first time I adjusted them I used a feeler gauge with .015 on it. I'm pretty sure it was mm, I checked with a .15 feeler after and it felt the same
@@xtcrider8270 not sure what’s up but I use inches to set mine. I set the intakes at .006” which I believe is close to .15mm. Also, there is an old saying “loud valves are happy valves”. That usually applies to old air cooled bikes but it has some merit with the big pig too. I don’t worry if mine are ticking a little. I worry more if they don’t make any noise.
On some engines it's due to different materials. I don't know what valve materials are used in a XR650R, but a lot of early CRF's wore their intake valves quicker than the exhausts because the stainless exhaust valves were just tougher than the titanium intake valves. I know you see way more carbon buildup on intake valves since they don't run as hot as the exhaust valves, so they can't self clean. Carbon deposits are incredibly abrasive. The carbon can't build up on the seat/sealing area because the valve is always slamming shut and that will keep it pretty much free of carbon, but I bet a bit of carbon makes it through here and there.
Thanks, helpful video. Reminds me of adjusting the valves on my Volkswagens ages ago. Same lash measurement as I recall.
I always thought that the intake valves go out of adjustment first because of the cooling effect of the air fuel mixture hitting them over and over. They cycle in temperature at lot more then the ex valves. Great video!
Could be.
When I was doing the valve adjustment on my 2007 RFS I didn’t quite get the nut tight enough on the left intake side and it came off, motor started ticking then died. E start just ticked and kick start was not budging, took it home and took it apart the nut got stuck in the cam chain. Luckily I got alway with just having to buy a new chain and nuts. Great content
Whew! That was a close one!!
@@highlandcycles yeah, great learning experience though now I know how to do a top end. The cost of an education
Thanks for the validation. I spent 20 minutes trying to get it to land on TDC, then I was thinking, why don’t I just roll the engine until the intakes are open and do the exhaust, and vise versa? Thanks man.
You bet
So does it really matter where it is in the stroke as long as the intakes are closed and I can move the rockers up and down? Can I adjust the intakes like that? My bike has no auto decomp
I am hoping a valve adjustment will get this big red pig to start. I’ve done the carburetor and it feels like it doesn’t have a lot of compression priming it.
I have the mechanics manual, and the shims just concerned about doing it myself
Ah, good old XR's! I'll always have a soft spot for them. Pretty similar top end as the RFS bikes. Shims are just silly.
Agree. If you’re going to ride a 4T it might as well be something like this.
Why can't the new bikes be this easy. I hate doing valve adjustment that much i always leave it in to be done. Great tutorial forthe xr guys🤙
Thanks. I agree.
Great video 👍🏻👍🏻👍🏻
Thanks
Thanks for the video
You bet!!
Good info thanks
Awesome
Is it natural to have some kind of valve noise, a bit of chatter? My exhaust valve were very tight about 0.003 less than spec, I put then to spec and I noise a chattering noise which was a bit more pronounced than before. I tighten the exhaust to maybe 0.007, let the engine warm and it seemed to help. Thinking I may have not use a feel gauge correctly (not coming at the side ) or perhaps the auto decompression affected my reading? The owner before me also put a higher compression piston and racing cam. Does the valves need to be tighter if that’s the case?
Some noise is fine.
What could happen if I went one size up to .007 on the intake gap
Nothing really. Would be fine
I heard .015 and .020 is correct gap..please help
No. Maybe .15 and .20 millimeters but not inches. That would be huge.
Why not check the gap before loosening the jam nuts?
What happend if one dont adjust on compressor stroke
You won't get the adjustment!
I would like to know how and when you fix the irratic idle issue you were talking about.
I’ll let you all know. I think my pilot jet could be the culprit too. It’s pretty big.
@@highlandcycles what size pilot jet do you have in it?
@@llecki I am pretty sure it’s a 68 but I need to check. That’s the problem with a bike that just works and rarely needs anything. I just don’t do much to it other than change the oil.
Put in the 68S pilot, it makes it idle and start and run better. Research it.
@@highlandcycles that's the way man, i chipped off about 10 lbs of dirt on caked motor of a xr500r, rode it for 10 year hard, it still is fine. intakes on a xr650r i've rode for a couple years now, runs like a beast, starts good is a tight .005 and exhaust is a bit loose from just checking at the tdc way, which might of been a bit off? i just put it back together and just gonna run it. or go the short route not worrying about pinpointing a tdc mark.
I would give this video 1000 likes if I could.
Thanks
Nice 👌
Thanks
What do you use to clean the engine off (in the spray can)?
That is brake cleaner
where is the decompression lever adjustment that's IMPORTANT!!!!
You just make sure there is free play in the cable. NICE ALL CAPS
how often should valves on xr’ be done?
Every 60 hrs ish
Hey highland. Trying to adjust my intake valves, I think I set them too loose before and they started ticking. I got to TDC the previous time I did them, they seemed a little tight so I loosened them to where I could fit 0.15mm feeler in and had a little drag. They weren't ticking before. I didn't touch the exhaust valves only intake. Started it up and it was ticking. Do I need to tighten them? Do you have a better explanation of how I know I'm in the correct position to adjust the intakes only? The intake valves are up and I can move the rockers up and down slightly. Is this the correct position?
I should mention the first time I adjusted them I used a feeler gauge with .015 on it. I'm pretty sure it was mm, I checked with a .15 feeler after and it felt the same
@@xtcrider8270 not sure what’s up but I use inches to set mine. I set the intakes at .006” which I believe is close to .15mm. Also, there is an old saying “loud valves are happy valves”. That usually applies to old air cooled bikes but it has some merit with the big pig too. I don’t worry if mine are ticking a little. I worry more if they don’t make any noise.
@@highlandcycles got it. I set the specs way too loose. Wasn't ticking before because they were too tight, ill fix it tommorow
What about the torque specs
I hope someone answers about why the intakes move and exhausts don't 🤔🤔🤔
Me too
@@highlandcycles yeah its counter intuitive actually intakes run cooler so would assume the exhausts would move more.... Baffling 🤣
It' could be that inlet valve and seat are being washed with fuel 👍🇬🇧
@@richardhartley7094 yeah. I’m thinking the impurities in the air and fuel are what does it.
On some engines it's due to different materials. I don't know what valve materials are used in a XR650R, but a lot of early CRF's wore their intake valves quicker than the exhausts because the stainless exhaust valves were just tougher than the titanium intake valves.
I know you see way more carbon buildup on intake valves since they don't run as hot as the exhaust valves, so they can't self clean. Carbon deposits are incredibly abrasive. The carbon can't build up on the seat/sealing area because the valve is always slamming shut and that will keep it pretty much free of carbon, but I bet a bit of carbon makes it through here and there.