head swap on XL80s with a newer XR80 head

ok guys, my first time posting here. i apologize if this has been discussed over and over, but i couldn't find anything to answer my questions real easily.  I am trying to rebuild an old Honda XL80s i had when i was younger for my son. We have had it running, but have since then, had to replace cam chain, both sprockets, one valve (thanks to cam chain slipping).  Now, after having it all back together and running for several months, the valves started ticking.  i readjusted the valves and it ran fine for a little while, now they started ticking again.  when i went to readjust them again, i see what the problem is; there is little or no oil making it to the top end and the cam journals have worn.  So i did a little research and found that a newer XR80 head will fit without any retrofit, as long as i have the appropriate head gasket for the year of head i am using.  i also have a newer cam and cam holder.  is there anything else i may need to make this swap?  i also purchased a newer oil pump to hopefully correct the oil flow problem.  i will thoroughly clean the block and screen when i have the cover off to change the oil pump.  How can i verify i am getting oil to the top without running the valve train dry for long?

Thanks for any help!  it's great to see my boy learning to love to ride as i did when i was younger.

It sound like a lot of money for OEM parts, I hope you found a good place to buy them.  I use ebay or partzilla.  For the oil, there is a bolt on the sparkplug side of the head.  While it's running, start to undo it.  Oli should start seeping out.  If you take it all the way out, oil will get all over you.  If no oil is coming out, your passage way is most likely plugged.  I've never seen a pump go out.  Also, is it street legal? 

i found some decent prices on parts and i think some are coming from partszilla. by now, i've probably spent more than the bike is worth, but for the time to work on it together with him, it's priceless.  it was street legal at one time, but i have no idea where the title is and the rear turn signals and tail light are long gone.

thanks for the info on the oil plug.  i will have to check it out.  sounds like it may be a good place to prime the system too.  when i have the head off, i will look to see where that oil passage goes and see if i can get anything through it.

When there's no oil going up to the head maybe the passage is clogged near or by the foot gasket.

When going into screen and pump, make sure the oil through thing and it's spring is right at place on the crankshaft. Without that you'll never get any oil pressure anywhere.

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Ok, guys!  Thanks for the replies.  I took the clutch cover off and removed the oil pump.  i found that when the main gear spins, the rotor part of the oil pump is not turning.  I bought one off of Ebay from a bike with less than 1000 miles and put that on.  Unfortunately, when i went to put it back together, after i put the new head, cam, cam holder, etc., the single head bolt that is outside the valve cover twisted off before i even got a change to properly torque it.  Not a big problem, i was able to spin it back out by hand after i removed the cylinder head again and pulled the jug off.  When i went to put it back together again, one of the oil ring sections caught and stretched it as i was putting the piston back in the sleeve.  So, dang the luck.  Now for new rings, rehoning the cylinder, and reassembling it all again. some days.....

i bought a kitaco or takegawa high flow oil pump for my xl100s and in  the instructions that came with it it shows how to drill out the oil supply journal in the side of the crankcase by the cylinder base for more oil flow to top end. the stock holes are like pin holes. oil pump was about 70$ Cdn so 40-50$ USD. 

https://thumpertalk.com/forums/topic/1155684-xr100-oil-squirt-mod/

Edited by CarmanCRF

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