One mod that can help is to use a new C3 rubber sealed bearing where one seal is removed so that as the oil goes into the side of the cam then nothing much is going through the bearing shield. It is shielded only to start with. Does need to be a C3 bearing to handle the heat. This gave me plenty of oil to the other side of the cam. Would be best to also have a Vitron rubber seal on bearing, but could not find such. I have a 1983 Honda XL600r and I think the newer XR650 comes with a rubber sealed cam bearing to help maintain oil pressure to the camshaft.
Not sure how much extra flow I got but I just drilled out the stock banjo fittings a little bigger. I think to 1/8", along the axis to the hollow bolt and also at the annular passage. Better than nothing.
I've got a snapped cam on one xl i bought which was a result of the previous owners not changing the oil which caused the inside cam getting gumed up inside starving the left hand bearing of oil and seizing up. Good tip drilling out the end cam holes I've drilled out the banjo bolts before.
I drilled out the tiny holes where the cam lobes sit in the casting .i took a # 2 center drill and slightly made them a bit bigger so the oil puddles up more and i have had good success ! if more oil puddles in a larger hole then more oil contacts the cam as well!
I did a similar thing to an '81 500 and it worked great. Thought about going through the cam like the 6's but ended up drilling passages in the valve cover side of the journals and then restricting the flow to the stock "cam bath". The oil pressure thru the stepped holes I drilled in the journals is basically floating the cam now. 1500 miles later and the cam still has its stock coating (NOS cam). No wear at all. Honda did the same thing later in the 3 wheelers so I figured why not? Plus the oil delivery tubes routed from clutch cover to valve cover (both tapped into the clutch cover and the valve cover) act as oil coolers too.
I bought a 1988 NX 650 with the same engine. I loved the style, the engine character, the torque. As far as handling it was a rail, however the engine didn't last too long. The top end ended-up being all worn out prematurely; Followers, cam shaft, finger ring of decompression mechanism.This RFVC Radial Valve system wasn't a good or robust mechanism. Mine ended-up being toast at 25'000 miles or 40'000 kilometers. That is the funny thing with Honda, normally, they make some really good engines, but from time to time, they also make some really crappy ones depending on which model ....Maybe there was a deficiency in the lubrication of that particular model, or the case hardening wasn't good enough. I have been wary of Honda valves mechanisms ever since. I would never buy a Honda with a Unicam system. The DOHC is the reason why I got a Suzuki V-Strom 650. For some reason only the Honda Factory 450 rallye has a DOHC ( with 64 horse power!!!) , but for the consumer grade stuff, they only sell the Unicam ( they probably make more money on it....:) I don't know why people claim they were bullet proof. I guess nobody kept them long enough to start running into problems. If they were so good from time to time you would see one with lot's of miles or something. I never did. They just seem to have disappeared! :). ruclips.net/video/Jb03TvDE8a0/видео.html
Hi Dave. I have the 1987 Honda XL 600 R. Great bike. I had low oil pressure to my cylinder head. I spotted a 1-1/2" crack in the back wall of my oil filter chamber. I believe a previous owner put the oil filter cover on wrong and built up pressure and cracked the rear wall. The cover can go on 3 ways. Only one way allows oil to flow to head. I fixed the crack with JB weld epoxy. Lots of oil flow to head now.
What kind of drills and size's did you use to drill out the cam holes,i can't get my NEW cobalt drills to do anything on my new cam,barely scratches it
Hi, interesting idea. I wonder, if facilitate te flow of oil to the head does not result in a weaker flow to the shaft and crank system? That could cause a dangerous weakened lubrication most important mechanism. Note, that oil passes the usual crossroads on two routes: the shaft and TOP. Is the right bearing of the camshaft U have/had sealed? If not, it may be a reason of poor lubrication of left side of the head.
Won't that lower the oil pressure? Yes,you might get more volume of oil up there,but you probably lowered the oil pressure by going to a larger diameter tubing. The cam lobes shouldn't really need any holes because oil collects in the cupped area underneath the lobes. It should be lubricating itself every time it turns ,the high part of the lobes should be dipping into the oil. Well hopefully it works. Maybe you have a failing oil pump? That could definitely cause a loss of oil up there. I had that happen on a 200x 3-wheeler once.
C'è molta guarnizione liquida che sicuramente ti avrà intasato il sistema di lubrificazione,la pompa olio è doppia di tipo trocoidale e funziona anche a 30 giri al minuto
Hi, I have an 84 xr200r twin-cam, known for doing heads. I have had the bike 20yrs hardly ridden it, maybe why it is still original. My 16yr boy wants to start riding it, I am hesitant due to the fact they like to do heads, and I think one day as so many destroy themselves it will be a wanted bike by collectors. Anyway, it has been years since you did the mod to the engine what was the end result? Would like to know as it may be a solution to letting my boy ride the xr200. Cheers.
Truth be told, if I had kept up on the oil changes like I was supposed to, I think it would of still be running. But I slacked and went way to far on the old oil and ended up having the connecting rod break on me. I was reading in thumper talk, about how someone else just put a bigger oil line and drilled out the the banjo bolts and went with a thinner oil cuz his was ice racing and that seemed to work good for him. If I had to do it over again I think I would've just done the oil line and banjo bolts, and that's it. Hopefully that helps you out
Install the tensioner in the head before you put the head on. todo this you need to make a little wedge tool to keep the tensioner in place while you install it
I have an xr650l, don't know if yours is similar but I used a zip-tie to hold the spring tight after compressing it on the side of the bench.. be sure to dry the oil off of the tensioner and spring otherwise the zip tie will slip.. then when it's in there use an exacto knife to cut it loose and pliers or a pick to pull the tie out.. works every time for me. Hope it helps!
One mod that can help is to use a new C3 rubber sealed bearing where one seal is removed so that as the oil goes into the side of the cam then nothing much is going through the bearing shield. It is shielded only to start with. Does need to be a C3 bearing to handle the heat. This gave me plenty of oil to the other side of the cam. Would be best to also have a Vitron rubber seal on bearing, but could not find such. I have a 1983 Honda XL600r and I think the newer XR650 comes with a rubber sealed cam bearing to help maintain oil pressure to the camshaft.
Not sure how much extra flow I got but I just drilled out the stock banjo fittings a little bigger. I think to 1/8", along the axis to the hollow bolt and also at the annular passage. Better than nothing.
I've got a snapped cam on one xl i bought which was a result of the previous owners not changing the oil which caused the inside cam getting gumed up inside starving the left hand bearing of oil and seizing up. Good tip drilling out the end cam holes I've drilled out the banjo bolts before.
I drilled out the tiny holes where the cam lobes sit in the casting .i took a # 2 center drill and slightly made them a bit bigger so the oil puddles up more and i have had good success ! if more oil puddles in a larger hole then more oil contacts the cam as well!
I did a similar thing to an '81 500 and it worked great. Thought about going through the cam like the 6's but ended up drilling passages in the valve cover side of the journals and then restricting the flow to the stock "cam bath". The oil pressure thru the stepped holes I drilled in the journals is basically floating the cam now. 1500 miles later and the cam still has its stock coating (NOS cam). No wear at all. Honda did the same thing later in the 3 wheelers so I figured why not? Plus the oil delivery tubes routed from clutch cover to valve cover (both tapped into the clutch cover and the valve cover) act as oil coolers too.
I bought a 1988 NX 650 with the same engine. I loved the style, the engine character, the torque. As far as handling it was a rail, however the engine didn't last too long. The top end ended-up being all worn out prematurely; Followers, cam shaft, finger ring of decompression mechanism.This RFVC Radial Valve system wasn't a good or robust mechanism. Mine ended-up being toast at 25'000 miles or 40'000 kilometers. That is the funny thing with Honda, normally, they make some really good engines, but from time to time, they also make some really crappy ones depending on which model ....Maybe there was a deficiency in the lubrication of that particular model, or the case hardening wasn't good enough. I have been wary of Honda valves mechanisms ever since. I would never buy a Honda with a Unicam system. The DOHC is the reason why I got a Suzuki V-Strom 650. For some reason only the Honda Factory 450 rallye has a DOHC ( with 64 horse power!!!) , but for the consumer grade stuff, they only sell the Unicam ( they probably make more money on it....:) I don't know why people claim they were bullet proof. I guess nobody kept them long enough to start running into problems. If they were so good from time to time you would see one with lot's of miles or something. I never did. They just seem to have disappeared! :). ruclips.net/video/Jb03TvDE8a0/видео.html
Hi Dave. I have the 1987 Honda XL 600 R. Great bike. I had low oil pressure to my cylinder head. I spotted a 1-1/2" crack in the back wall of my oil filter chamber. I believe a previous owner put the oil filter cover on wrong and built up pressure and cracked the rear wall. The cover can go on 3 ways. Only one way allows oil to flow to head. I fixed the crack with JB weld epoxy. Lots of oil flow to head now.
I had the same issue on my '84 xl600r. Used some devcon aluminum putty and its as good as new.
What kind of drills and size's did you use to drill out the cam holes,i can't get my NEW cobalt drills to do anything on my new cam,barely scratches it
Hi, interesting idea. I wonder, if facilitate te flow of oil to the head does not result in a weaker flow to the shaft and crank system? That could cause a dangerous weakened lubrication most important mechanism. Note, that oil passes the usual crossroads on two routes: the shaft and TOP.
Is the right bearing of the camshaft U have/had sealed? If not, it may be a reason of poor lubrication of left side of the head.
Won't that lower the oil pressure? Yes,you might get more volume of oil up there,but you probably lowered the oil pressure by going to a larger diameter tubing. The cam lobes shouldn't really need any holes because oil collects in the cupped area underneath the lobes. It should be lubricating itself every time it turns ,the high part of the lobes should be dipping into the oil. Well hopefully it works. Maybe you have a failing oil pump? That could definitely cause a loss of oil up there. I had that happen on a 200x 3-wheeler once.
C'è molta guarnizione liquida che sicuramente ti avrà intasato il sistema di lubrificazione,la pompa olio è doppia di tipo trocoidale e funziona anche a 30 giri al minuto
Do you worry about breaking a cam from drilling the oil passages out ? Apparently it works, is she still going strong?
And what size did you drill the holes out to
Hi this is a good mod! What did you use to make the oil pipe? Size etc as I'd like to do the same. Thanks Huw
¼"o.d. copper tubing and some brass fittings
Change oil regularly and don't ride it low on oil. No need for all that extra work lol.
Hi, I have an 84 xr200r twin-cam, known for doing heads. I have had the bike 20yrs hardly ridden it, maybe why it is still original. My 16yr boy wants to start riding it, I am hesitant due to the fact they like to do heads, and I think one day as so many destroy themselves it will be a wanted bike by collectors. Anyway, it has been years since you did the mod to the engine what was the end result? Would like to know as it may be a solution to letting my boy ride the xr200. Cheers.
Truth be told, if I had kept up on the oil changes like I was supposed to, I think it would of still be running. But I slacked and went way to far on the old oil and ended up having the connecting rod break on me. I was reading in thumper talk, about how someone else just put a bigger oil line and drilled out the the banjo bolts and went with a thinner oil cuz his was ice racing and that seemed to work good for him. If I had to do it over again I think I would've just done the oil line and banjo bolts, and that's it. Hopefully that helps you out
also replace oring at oil pump
Wheres that located as I'm just doing a top end on my xr600
How do u put in the cam chain tensioner
Install the tensioner in the head before you put the head on. todo this you need to make a little wedge tool to keep the tensioner in place while you install it
I have an xr650l, don't know if yours is similar but I used a zip-tie to hold the spring tight after compressing it on the side of the bench.. be sure to dry the oil off of the tensioner and spring otherwise the zip tie will slip.. then when it's in there use an exacto knife to cut it loose and pliers or a pick to pull the tie out.. works every time for me. Hope it helps!
Cringe.
How come?