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Discussion Starter · #1 ·
I know this has been discussed before, but the search doesn't work and I need some answers. I have already done the PAIR removal and the flapper valve removal but here lately I've noticed this noise that sounds like the lifters at the lower RPM range. My bike seems to run smooth and tight in the mid/upper RPM range so I'm wondering what this might be? My bike currently has 6700 miles and regular oil changes around 1500~2000 miles each after the first 600 mile oil change/checkup.

If I could look it up I would....

TIA

-E.
 

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injectors make noise as well. i can hear mine at low rpms, cause the engine drowns them out at anything higher than that.
 

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Fyi

By the way you don't have lifters. The cams ride directly over the valve stem. The lobes push on a cover called the bucket which has a shim under it that rests directly on the valve stem. Shim and Bucket system. Some times the shim is to small or big causing value lash (small) and unseated (big). Yes the valves can stretch or the seats get damaged. If you flog this motor new and use low octane you could have done this. Though its not likely. Furthermore since you said lifter you may not know the cams are gear driven thats the cool whining sound.
 

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Discussion Starter · #5 ·
EvilTwin-05 said:
By the way you don't have lifters. The cams ride directly over the valve stem. The lobes push on a cover called the bucket which has a shim under it that rests directly on the valve stem. Shim and Bucket system. Some times the shim is to small or big causing value lash (small) and unseated (big). Yes the valves can stretch or the seats get damaged. If you flog this motor new and use low octane you could have done this. Though its not likely. Furthermore since you said lifter you may not know the cams are gear driven thats the cool whining sound.
I don't profess to know everything about the RC engine.. I was just trying to describe the noise so that people would understand what I was talking about. Like I said I know this has been brought up before and I would look up the info if I could. I'll look into some things, thanks for the information guys.

-E.
 

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wellllllllllllllllllllllllllllllllllllllllllllllll llllll

I can only guess as your discription is pretty vague.

6700 miles it is probable yet unlikely that you may have some valve lash issues. If you are sure that you have no exhaust leaks you need to do a little detective work.

Start the bike and bring it up to temperature. now ith the bike idling and on a work stand or even the side stand use a 3 foot long piece of vacuum tube as a stethescope (sp?) and do a little detective work. Locate precisly where this sound is emenating from. then get back to me.
or pm me your phone number and I will call you and figure this out with you
 

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Veins, I wasn't flamin ya. Or implying that your in anyway a dumb arse. I was was just passing some info you might find helpful. So no worries. Good luck with the noise it is puzzeling.
 

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Discussion Starter · #8 ·
sp2pilot said:
I can only guess as your discription is pretty vague.

6700 miles it is probable yet unlikely that you may have some valve lash issues. If you are sure that you have no exhaust leaks you need to do a little detective work.

Start the bike and bring it up to temperature. now ith the bike idling and on a work stand or even the side stand use a 3 foot long piece of vacuum tube as a stethescope (sp?) and do a little detective work. Locate precisly where this sound is emenating from. then get back to me.
or pm me your phone number and I will call you and figure this out with you
I started it up and went for a ride this evening.. Before I got on the bike I noticed some noise coming from under the seat and around the mid-pipes. I may in fact have an exhaust leak so I'll have to look into it more tomorrow. BTW, the lifter type noise I was referring to is when I am taking off from a light and the bike is under load at lower RPMs it sounds as if something is clacking for a few seconds until I get up higher in the RPM range. That's about the best way I can describe it.

Thanks for the help guys.. I'll let you know what I find out.
 

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Discussion Starter · #9 ·
EvilTwin-05 said:
Veins, I wasn't flamin ya. Or implying that your in anyway a dumb arse. I was was just passing some info you might find helpful. So no worries. Good luck with the noise it is puzzeling.
I know you weren't flamin.. NP man.

:D
 

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Digging up and older thread as i am having the same problems...

What should i look for as far as what a valve problem sounds like (besides the obvious ticking from the valve cover). Bike has 8500 miles, i have only put 700 on it since i bought it. Previous owner had bike checked before i bought it at a dealer and it had no issues. I performed an oil change right after i bought it to be on the safe side, Mobil 1 gold cap, that i saw many people post they use, and honda filter.

To me it sounds like electricity arcing with the RPMs of the motor. Which is why i am leaning towards injectors. However if it is a valve adjustment problem i would like to take care of it. What is the correct torque spec on the header bolts, bike didnt come with a manual.
 

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So after using my screwdriver as a makeshift stethoscope, i dont think my problem is valve related. The only thing i heard in the heads was chain whine. However when i listened right under the waterpump, between where it is stamped HRC and the cover thats where i am hearing the ticking. Actually it is sounding more like a bit of a knock. Any insight would be really appreciated.

When i did the oil change it came out as clear as the new oil, no shavings, nothing.
TIA
 

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what octane gas? Do you have a power commander "R"? Whats the idle?

Water ppumps knock when going bad but I don't think I could hear it over the gear drive. Sounds down that low could be a bottom end noise resulting from one of the above questions. Doubt its a bearing. you can alway tach it up to 10.5 and see if it comes apart or makes more noise.:rolleyes:
 

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ok.. i've flogged a honda superhawk for 32,000 miles and tore it down.. heres what i found after hearing the EXACT same knock your describinig and my theory on it..

valves, buckets, lifters, everything all within spec.. i mean EVErY VALVE.. the odds that your RC will have valves out of spec AT ALL....EVER.... are slim to none.. most honda engines i've ever spec'd (inline fours especially) are very very well built and hardly ever need valve adjusting

both cylinders within .05mm out of round/taper no scoring
both pistons looked well, no bad scorching or skirt damage, but were slightly out of spec (skirt to skirt) the likelyhood you're hearing piston slap is nil

connecting rod plain bearings had some scuffing on them, presumably the knock i heard near the crank, lower in the motor and only when low revving the motor away from a stop light... i can only theorize that during low rpm operation, these huge pistons overwhelm the oil surface under low rpm pressure and cause a hydraulic knock or an actual metal to metal contact on the con rod big end... my advice for you, stop lugging the motor, give her some revs like she wants and ride the rc like you mean it..
:D:twocents
 
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