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  1. Motorhead

    CB750K DOHC oil "sweat"

    Thanks for stepping in. Ring wear would first result in engine burning oil, wouldn't it? There's absolutely no smoke from the exhaust whatsoever.
  2. Motorhead

    CB750K DOHC oil "sweat"

    My bike developed oil leaks and oil "sweat spots" in all sorts of places (mostly drive sprocket seal, vertical camchain tentioner rear bolts, oil pressure switch etc.), all as if there was excessive crankcase pressure. There was also such a "sweat spot" where the right vent tube connects to the...
  3. Motorhead

    Head gasket leaking - "Re-torque"?

    It's been a while since I've noticed black gooey build-up at the front of the head gasket. Since I know that there are no oil paths under pressure going through inside the head (the oil line is behind the cylinder block/head between no. 2 and 3 carbs), I assumed I was due to rich fuel and bad...
  4. Motorhead

    Left engine cover leak (the one that contains the starter clutch)

    Well, Looks like this specific problem is solved for now. I "backed" the grommet with some Victor Reinz RTV from the cover side (the rounded side of the grommet) in a way that the grommet mating face was a bit above the cover edge. Then I let it dry completely before tightening the cover. So...
  5. Motorhead

    Left engine cover leak (the one that contains the starter clutch)

    Yep, my grommet is pretty much in the state of the one in the picture. Let's consider the problem narrowed down to the grommet being compressed over time and now not providing the same tension of seal against the paper gasket/engine case mating surface. It didn't look as if the oil was...
  6. Motorhead

    Left engine cover leak (the one that contains the starter clutch)

    It was bone dry when I applied Hondabond 4 to it and then let it sit for 24 hours before starting the engine. It supposed to be oil resistant once it's cured, isn't it? Maybe Victor Reinz Reizosil could be better for this? Or the blue polyurethane compound from the same maker? With, or instead...
  7. Motorhead

    Left engine cover leak (the one that contains the starter clutch)

    I'm pretty desperate at this point. There's a little rubber insert to pass the pickups' wires through. This grommet forms a line with the cover's mating surface, against the engine case mating surface. (It's not the three-bolt "points" cover) So the cover's paper gasket always leaks from...
  8. Motorhead

    Moderate Front End Upgrade

    Meaning, I will also need a different front axle, and the calipers might need to be re-centered?
  9. Motorhead

    Moderate Front End Upgrade

    Lately, the rust spots on my fork tubes have started spreading, it looks like they're up for replacement. What I have on the bike right now a complete front end off a 1980 CBX1000A - 35mm forks, with a Telefix fork brace. A few years ago I also have installed Race-Tech springs and...
  10. Motorhead

    Upgraded clutch springs

    Thanks amc49, Look here, http://www.dynoman.net/engine/clutch/barnett.html Complete sets from Barnett, with their springs, friction discs, and steel plates albeit only 6 steel plates. They probably assume I keep the OEM double plate. Maybe I should order the sets and ask for 2 extra steel...
  11. Motorhead

    Upgraded clutch springs

    Hi all, hope you're all well! After a lot of miles on it, my clutch started slipping under hard acceleration and it looks like friction plates and springs replacement is due. I intend to use OEM friction plates, as I always did. Would you recommend installing stronger clutch springs, like...
  12. Motorhead

    Shortened chain - shortened wheelbase

    Exactly, I have clip-ons. I have a CBX1000A front end.
  13. Motorhead

    Shortened chain - shortened wheelbase

    Thanks amc49. Yes, I did check the slack off the stand with a friend on the bike. The chain wasn't of the endless type (actually, I have never seen an endless replacement chain here), I ordered 108 links including a master link which they rivet on the bike at the shop, so making the job easier...
  14. Motorhead

    Shortened chain - shortened wheelbase

    Hi all, hope you've been all doing well. Today I went to a shop to replace the driving chain (the only service I don't do myself). I have ordered a 108-link chain as per the manual (530, 18/46). After the job was finished, the young mechanic has proudly announced that my chain was too long and...
  15. Motorhead

    Oil leak from behind the right engine cover

    Of course it's the LEFT side cover, just corrected the post.
  16. Motorhead

    Oil leak from behind the right engine cover

    Hi there all, hope you've been well. It's since long ago that I have an oil leak from where the ignition pickups' wires pass, in the rear part of the left side cover (not the "points" cover, but the one behind it, on which pickups are mounted). There's a rubber grommet moulded on the pickups'...
  17. Motorhead

    Hi from Montreal from me and my non-starting '81 CB750

    The bike looks great, must have been taken a good care of. Are these lowered rear shocks? Good luck!
  18. Motorhead

    CB750 1980 unburnt fuel

    These are my compression test results: #4 170+ #3 165- #2 165+ #1 170+ So your guess about the valve seals is probably correct. I am now recording every time I add oil, so in about 4000 km I'll be able to tell, how much it uses exactly between changes.
  19. Motorhead

    CB750 1980 unburnt fuel

    [emoji106]
  20. Motorhead

    CB750 1980 unburnt fuel

    No flash on photo, the colors look true. So, would the board recommend, say, 1/4 turn out on the idle mixture screws? My main jets are stock keihin #68.
  21. Motorhead

    CB750 1980 unburnt fuel

    These are the plugs 1-->4 (left to right). Does no. 3 look a bit lean? BTW, I think there was a way to tell, how the engine performs on high or low rpm (or throttle positions) by looking at different areas of the plug, or was it an urban legend?
  22. Motorhead

    New project

    Good luck!
  23. Motorhead

    oil cooler/mini fan

    Thanks AMC, I'll try to tighten the clamps some more. There's no room to fit two clamps of that width. I got the clamps at the same hydraulic shop, supposed to be of better quality. The hose has some thermal insulation material, as you can probably see in the middle pic. This stuff is VERY...
  24. Motorhead

    CB750 1980 unburnt fuel

    Dave, 100/90-19 IS stock. Could your clutch go thin BECAUSE of the gearing? I like having enough torque on tap in any gear. My clutch plates are about 40000mi old and spinning the rear wheel is the only "slipping" it does :) The trade off is optimal cruising speed of just 80mph (@~6500rpm)...
  25. Motorhead

    oil cooler/mini fan

    Just done. Derale oil cooler with internal termostat which blocks off 2 rows out of 3 when the oil is not hot enough, Cycle X oil filter adapter with oil cooler outlets. The fittings at the adapter end were pressed on lines by a local company which fits lines to heavy hydraulic equipment, my...
  26. Motorhead

    CB750 1980 unburnt fuel

    And what is your front wheel size? Did you change it too? Did you measure speed with the bike's speedo or GPS? How did the bike accelerate?
  27. Motorhead

    CB750 1980 unburnt fuel

    Slowing down increase in oil consumption is good enough for me at this point, as is anything else that would postpone any major head/cylinder job that would be a lot of hassle in my circumstances. That means lowering the final ratio by about 10% (from 2.55 to 2.33). It is tempting to have the...
  28. Motorhead

    CB750 1980 unburnt fuel

    Anyways, I'm about to take the Saturday to clean the carbs. When I think of it, last time I cleaned them, was about 3.5 years ago.
  29. Motorhead

    CB750 1980 unburnt fuel

    [emoji4] Dave, are we talking about the same bike?))) Mine has 18/46 which is the stock ratio of 2.55. Its roughly 65mph @ 5000rpm at top gear, with a top speed of 200kph (125mph). 7000 rpm in top gear is only about 140kph, no big deal of a speed. This bike is pretty slow overall, to be...
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