Airbusboy

UPDATE.... I wasn't happy with the smoke coming from the exhaust. Overly worn valve guides I assume from the lack of oil during my screw-up. My solution was to buy the Rancher Big Bore Kit that included the head assembly off the Ebay dealer at about $240. The kit arrived and quality looked good. I did the swap and she fired up nicely. The kit took it from 329cc to 355cc. I've already noticed an increase in power during the break in period and no smoke! I've changed the oil and filter 3 times already and find very little (and decreasing) substance stuck to the tip of the magnetic oil plug and zero visible particles in the filter pleats. Oddly, she is running better than ever. I plan on changing the oil and filter one more time before hunting season starts and after that....roll the dice, but so far, she looks good! Thanks for all the help, folks!

Update..... I think I pulled it off. She runs excellent. Good power. Revs nicely. Idles smooth. SLIGHT smoke if it idles for a while then I 'blip' the throttle, but then it clears out and she runs clear. I DID install a magnetic oil plug and when I changed the oil/filter after about an hours' worth of run time there was a small amount of black goo stuck to it. It was almost the consistency of super-fine/600 grit valve grinding compound. I plan on changing the oil/filter again after she's been run about another 5 hours or so, then space them out to normal intervals. A hearty 'THANKS' to all you guys for the help/guidance/advise, although Honda might be mad at you for killing a potential sale of a new one!

Well, so far so good.Top end rebuilt and flushed. Valves adjusted. Compression checked at about 85 psi. Oil confirmed being pumped 'upstairs' and through the valve cover galley. Ran 3 carb-bowls full of fuel, then changed oil and filter. No metal found in filter upon examination. Put everything back together and filled with oil and new filter. Ran her around my yard for about 15-20 minutes. She sounds fine. Good power. Revs up normal. Nothing unusual. Tomorrow I plan on taking her to camp and running her for an hour or so, then change the oil and filter again and let her go. Fingers crossed. If my top-end rebuild and flush doesn't work, what do you think will be the first signs? Compression loss? Power loss? Noisy bottom end? Noisy top end? Hard shifting?

Yep. Been a Honda fan for many years. Prior to this my biggest pain on a Honda has been the 4-in-a-bank carbs on the old air-cooled Honda Fours. LOTS of specialty tools for those but it's worth it to see a modern crotch rocket shocked to see my 38 year old CB1000C show 'em my taillight. Unbelievably smooth and powerful. The parts for the Rancher should be in about a week from now, right after hunting season ends. Ain't that the way it always goes? LOL. I'm rather optimistic.

While I wait for parts, I have been studying the service manual and I have a question....Is the oil pump fed FROM the filter housing or from/via the scavenger pipe? The reason I ask is 'IF' it is fed FROM the scavenger pipe, which I suspect, then the pump never ran dry in my case, only the upper cylinder/rockers. And IF that's the case, then perhaps the pump did not sustain much, if any, damage. I also want to clarify...I use this machine to go from my hunting trailer to my deer stand and back, that's all. The time each way is about 5-7 minutes, and then it sits for several hours. Plus I don't abuse it when I do run it. My point is that it barely gets up to operating temps and never really gets 'hot'. With that in mind, perhaps the upper cylinder damage is minimal and I MAY get lucky. I plan on gently wiping the entire upper area 'upwards' from the pushrod cavity with a oil dampened sponge to remove any metal that could be laying there. After several swipes like that, I'll slowly pour some light-weight oil down the entire upper cylinder with the oil plug out, letting it flow straight out and not sit in the lower case. After a few quarts, I'll put the plug back in and fill it up to normal capacity with oil. Without attaching the gas tank, run it long enough to use all the fuel in the carb bowl, then remove the valve cover to confirm oil IS being pumped 'upstairs'. Assuming it is, reassemble all of it, plastics included, and run it for about 30 minutes, then drain it and change filters. I'll do that a few times, then if she's still running proper, fill it with good oil and let her go with my fingers crossed. And IF I find that oil is NOT being pumped upstairs, then perhaps JUST replace the oil pump, assuming I can find one, and then do the above procedure. What ya think?

Thanks for the info. It'll take about 10 days to gather all the parts. I'll post again when I'm done.

I checked. The exhaust rocker that contacts the pushrod is slightly more bright-polished than the intake, but no deformation. Valve stem contact points are normal.

Well guys....I checked the filter that I removed. It was an 'Emgo' brand and the ONLY writing on it was 'TOP' printed on the outer side. Still, I should've known that it should have gone to the outside. This is the electric shift model and that tells me that I also need to be concerned that any possible metal MAY have gone there (transmission) as well as the bottom end. Oh goody. I didn't take an pics of the rocker assembly cause there is no damage to see, only feel. However, here is a pic of the top end of the exhaust pushrod. I've had this thing so long that I can't remember but I THINK I did install a magnetic oil plug. I'll find out for sure when I drain it. I also plan on straining the oil through a white coffee filter to see if I see any chips/metal. Keeping my fingers crossed.

yes, it has an oil cooler.

Yep. Plan now is to replace the entire rocker assembly and the pushrods. Inspect as best I can without pulling the cylinder. If nothing jumps out at me, fill/flush the motor several times, then just run it and see how she behaves. Nothing to lose. With no oil going topside, is it possible there was minimal 'wash-down' of metal down into the lower case and MAYBE she'll be okay? Of course, the extra pressure on at least the exhaust pushrod and cam lobe MIGHT have some damage directly. Does this machine have a magnetic oil plug that may have captured some metal and minimized the damage? FYI ... there was no visible galling of metal or damage to the rocker assembly at all, only a 'rough' feel as I manually moved the rocker(s) on the pivot rod. The only visible damage was the slight mushrooming to the top of the exhaust pushrod. With that in mind, I'm gambling on about $100 worth of parts/oil/filters and roll those dice.... Thanks for your thoughts and guidance here, fellas.... I've restored several OLD Honda motorcycles over the years, the best one being my 1983 Honda CB1000C so I'm not new to wrenches, just terribly embarrassed that I caused this mess of my own accord. Can I say I must've been drinking at the time and gain some sympathy? LOL.

Well....Dang. Filter WAS backwards. The rest of this machine is pristine so here's what I'm going to do. Rebuild the rocker assembly, replace the pushrods and reassemble. Flush the motor interior several times, then drive it till it dies. I bought her new and added the winch and Warn 2/4 splitter. It's 17/18 years old and I've gotten many a mile and smile out of her so when she dies, I'll part her out and get a new one. Lesson learned. I have NO idea how the filter got that way. I now have a sore back and gained knowledge. Thank you to all for the help in figuring this out! Out of curiosity...is it difficult to find new engines for these and is it hard to swap 'em out? (in case I get a wild hair).

I'll be pulling the filter in the morning to check for a reversed installation. How can I check the oil pump to see if it's working? Is it removable? The motor was not run long since it's last oil/filter change, maybe an hour or two.

Assuming I go ahead and rebuild the top end...I'll need two rockers, one rocker shaft and two push rods, right? Anything else? Does that rocker shaft come out easily?

Okay. ASSUMING I find the filter was in backwards (I'll check tomorrow), if I see no metal in the top end, and filtering the current oil I find no metal and do a flush or two with new oil/filter, is the bottom end splash-fed and would it be safe to assume the bottom end is good, then add new rocker assembly and new push rods and fire her up?

Okay. A few questions. 1) What will I see when I pull the filter 'IF' it was installed backwards? 2) 'IF' it was installed backwards, could that have restricted the flow and caused my issue? 3) Does this engine have an oil pump that I should look at and evaluate? 4) Has anyone used the 'Big Bore Kit' with or without the new head? Is it any good? 5) Can the rocker shaft/rockers in that upper assembly be replaced seperately or is that a one-piece assembly?