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Discussion Starter · #1 ·
Well, finished my major overhaul on the engine, cleaned the oil pump and tightened chain, tripple bypass and new oil seal, and starter motor rebuild. Put it all back together and all moved/worked well. Put it on the bike and started testing it out. Filled the fluids and squirted some oil in each cylinder, then turned it over by hand using crank bolt for a few dozen revolutions. Cranked the engine with the plugs out and all worked well, so I cranked it for about 3 seconds at a time until I saw the oil light go out. Put the plugs in and again cranked it (kill switch) and sounded good, cranked fast and oil light went out while cranking .... well, looks ok so far.



Put the tank on and hooked it up, open petcock and put choke on. cranked twice and it sputtered a bit and started right up, shut it down after 35 seconds (no exhaust). Put the exhaust on and started it up with the rad cap off, ran VERY smooth and didnt need chock after about a min. Warmed it up to operating temp and watched the fan come on once it just passed the thin/thick line by about 1/4".



So far all seems really good, so put it together and threw the seat on and went about 1 mile to Crappy tire to buy a push in fuse holder for the fan (replacing round one under seat and putting a push in one where the tool kit must have gone behind right side cover). During the ride the bike was vibrating to the point I was worried. To me it "felt" like somthing shaking .... actually like the crank shaking. The engine stayed at the thick/thin line all the way there and back with the fan rarely comming on (and its hot here today). I found the heads very hot but within normal temp according to the heat gun and guage.



After doing the fuse I started it again and let it warm up and run for about 1/2 hour. It sounds fine I guess (remember, this is the first time I have had working mufflers on the bike), sort of like a sewing machine on some super steriods. I decided to go for a short ride and see whats what. Seemed fine, and since I was alone on the road I opened it up to see if it would go "BANG!" I noticed that bike doesnt bog down anywhere near where it did before the repairs, and will accelerate fast out of a 40KPH ride in 5th. Took here about 2 miles at 60 KPH, temp normal, but the shaking/vibration seems to be when Im getting close to the shift RMP (I have no tach so no idea what RPM it is). On the way back I went down an open stretch (limit 80KPH) and without opening up fully, I cranked it most of the way open and the bike shot off really good. Before I knew it things were a bit blurry so I checked the speedo....pinned at 80MPH and going strong....slowed back down as it wasnt my intention to go that fast. Got it home and temp was fine and it sounded fine, just not how I remember it sounding.



So, am I being paranoid here. I know the bike did vibrate when I got it (not a wabble, just vibration like a massage chair on steraoids) but dont seem to remember it being this noticeable (although been a while since I rode it). I am sure if I had a bearing problem the engine would be dead already. So, can anyone think of anything I could have messed up in the bypass to give me this sensation of a crank flopping all over the place. Even checked the cam for rubbing on the fan ... nope, over 1/2 clearance. Not the valves or any loose bits. I need to find someone with a vid camera to see if anyones good ears can spot something.



Thanks all, it may just be my paranoia here, but the bike seems like its performing too good (especially since I know its running rich).
 

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You say you had no "working mufflers" before,,,was the bike really loud before?



How much did you drive before you did the work on it?



Sometimes if you drive a car or bike with no muffler for a while, once you get a muffler installed you may notice things that were not noticeable before.



Other than that,,make sure all the engine mounting bolts are in place and secure.
 

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Discussion Starter · #3 ·
Yea Allan, when I got the bike and rebuilt it, the original mufflers were a mess. Seems the PO drilled out the rivets, but couldnt get the baffles out, so he ripped a few bits of the back out. One was very badly rusted inside and most of the inside baffle was gone, the other one left the bike on the 401 and was never seen again. So most of the 2 years I have had this bike its been H-box and baffle-less stock shells. I would say before I did the stator fix I put maybe 1200 miles on it, mostly just short trips and a few 200 mile ones.



It was when I got the soft tail dayna mufflers and put them on that I tried to start the bike to hear then and had a dead battery (dead stator). so I have not rident the bike WITH mufflers before this engine out work. Engine bolts are all good and even tripple checked them (and most of the other bolts). Trying to listen to the sound and get a location is hard, seemed like it was comming from the water pump housing, but also from the rear bottom and the cluch basket. I know that I checked the engine a lot when it was together for any rubbing or other noises, and everything was fine. Even though for a moment when checking it was the stator rubbing the rotor.



Really hard to describe, but my initial gut feeling when driving was the crank bearings were shot, that deep clunking type of vibration. After a while I ruled that out as the vibration get a bit stronger with higher RPMS, and really not there at idle (opposite of a crank). Plus, at 90+MPH if it was bearings they would have shattered. For all I know it may be a normal engine noise that im not used to (after having nasty annoying pipes all this time). Its baffling, as the noise to me sound like something majorly bad, but the bike outperforms itselof since the repairs ????
 

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You didn't lose a magnet on the rotor?
 

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Discussion Starter · #5 ·
Well, only if it came off after install. I checked the rotor before I put it back on, mainly to make sure it was clean and didnt pick up and metal bits or filings. I also metered the stator before connecting it in, and got 45VAC on all legs at idle (which i think may be about 900, not sure the meter I have wont give me a good reading and my tach is toast). When connected the bat sits at 13.58VDC (battery was fully charged before putting back in bike).



It doesnt really sound like something flying around, but almost like a weak version of a washing machine that is unballanced and starts to bounce a bit, only a lot faster frequency. Maybe tomorow I will check the drive shaft and see if I messed up anything there. Know the pin is screwed in and tight.
 

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Discussion Starter · #7 ·
Good idea, will run a check tomorow. If that turns out OK I will try getting the mixture set right, just hard when the tach I have doesnt seem to work well on this bike (its a multimeter with tach/dwell and a tone of other stuff), and has settings for 3 - 8 cylinders. I also think the pick up (clips on spark lead) doesnt work well as you can only get it so close to the plugs in these engines.
 

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Run the tach on 4 cylinder and you need to either double or halve the figure the tach gives you.



I.e., if you're showing a 550 RPM idle you need to double and halve if the idle is showing as 2200 RPM.



Sorry, I can't remember which off hand but it should be fairly obvious.



Also, have the carbs been balanced yet?



EDIT. I think the CX is a redundant spark system, so may read as a 4 cyl. on your tach.
 

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FADM, I'd be willing to bet that the reason the mention of the loud pipes earlier was to check if the vibration noise you now feel was hidden by the loud pipes. It may just be what you are feeling is quite normal in a good running bike. If you take into account these are twisted twins, by their very nature are torquey in a different plane than a V rod, and it's not abnormal for certain minor twisty feelings to be played out during a ride. You've had a few good runs on it, and never when it ran this good. So it seems to me it is just the newness of it.



I'd still keep checking your work, but from what I've read, I don't think you have gone too far astray from a good rebuild.



Fingers crossed for ya'.



Joel in the Couve
 

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Snr stern.yes as said,double check the drive shaft is fullly located.

i cant see that you have messed up anything within the bowel of the engine,because you werent there.

any exhaust or carb intake leaks?



any member living close?

 

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How much vibration would an imbalanced grinding job on the end of the crank (new electric fan right?) give? Just a shot in the dark. If it's an RCH heavier on one side, would that cause that much vibration?



I don't really know, just grasping at straws.



Fib
 

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Have you checked/balanced the carbs?

If they drift out too much it can feel like you have

2 250 engines instead of one 500 engine




They don't have to be mismatched by much before vibration is excessive. It can be time consuming and frustrating to get them right, but is time very well spent.
 

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Discussion Starter · #14 ·
Well I am going to ballance the carbs, as it has never been done since I had the bike. I checked the best I could for carb leaks, but I ran out of carb cleaner so used a propane torch with all beahiving well. Going to pick up another can of cleaner if I can find a Crappy Tire that has one lol. As for the cam grinding, I am sure its not 100% ballanced, but the amount it could possible be out would be extreamly small considering its total mass and the amount ground (probabaly closer now that the left over gear teeth have been removed).



I have actually bought 4 vacuum gauges from Princess auto and going to make a 4 guage unit (so I can also do the Goldwing when I start on it), I just need to pick up or make some adaptors for the intake hole.



I have tried using the tach on the 4 cylinder scale and it is probabaly reading right, but the readings jump all over the place (problem of being a digital meter). I also know the reading is greatly effected by the clip on pickups possition (as its supposed to be as close the the plug as possible). Not sure if the TI engines have resistors in the plug caps, but if they do that could also be effecting the pickup. May need to find a cheap clip on tack that has an analouge display on it, then maybe I can get a better idea of the real RPM value.



Think today I will ride it around and see if I can find some adaptor that will fit the vacuum take off holes, if not I will just get some bolts and lathe them down to an adaptor and make a pin hole in them (to act as a restrictor)
 

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How much vibration would an imbalanced grinding job on the end of the crank (new electric fan right?) give? Just a shot in the dark. If it's an RCH heavier on one side, would that cause that much vibration?



I don't really know, just grasping at straws.



Fib




Hmm, I would like to know the answer to this too. My camshaft was definitely ground unevenly, and is very obvious when glancing behind the radiator to peek at it spinning. I wonder if that could potentially cause any issues.
 

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Hmm, I would like to know the answer to this too. My camshaft was definitely ground unevenly, and is very obvious when glancing behind the radiator to peek at it spinning. I wonder if that could potentially cause any issues.


I highly doubt it.There is no mass far outside the cam-shaft to cause vibrations,unlike a faulty Mechanical fan.More likely loose engine bolt or possibly carbs or if road speed related other issues.
 

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Discussion Starter · #17 ·
Wel, I have to say a big thanks to everyone
youre the best.



Decided to take it to Brafaso and see if I could get some adaptors (or something I could make them with) for the carb vacuum port so I could sync the carbs. Well, as I got there I just kept going LOL (missed my bike). I ended up going on a 2 hour 30 miles ride. First part was nasty stop and go trafic jam for almost an hour (not to fun in full gear and being 90 deg outside). The engine never got bast 1/2 way on the temp gauge and the fan did a great job. I then spent the other hour coming back, most of the way was 100KPH (60MPH) with a 3 mile stretch at 140KPH (80 MPH). The bike performed better than it ever has, and seemed fine.



I think my big problem is the engine seems to make a "whining sound" which is probably normal (couldnt hear it without mufflers on) which is only noticeable at higher RPM. I think some of what I though was knocking is a low end noise from the mufflers. I know it was running rich before I put the mufflers on (plugs were black sooty) and probabaly still are (although it seems to perform far better than before, and I thought it was good before lol).



Now that I am fairly sure there is nothing wrong with it, Im going to turn up the carbs and ballance them (if I can stop passing Brafasco on my rides lol). Think Im going to get my vacuum gauges (picked up 4 from princess auto last year) and mount them to a plate and then calibrate them all, that way I can do the CX and GL when I get around to looking at it. (may be a while, I want to ride lol)



Again, thanks all, as I know if I had followed the manuals alone I would have made a lot of mistakes along the way (not heating copper washer, not touching the olo mint, missing the polo washer, not rounding the stator posts .... the list goes on).
 

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You are now hearing the famous,"Honda Whirr" from the cam train.When riding with other riders they have said it sounds like a small Jet engine when I overtake them and they love it.This is not to mention the lovely V-Twin sound the bikes make




Also bet you are glad you did the Efan conversion.They really come into their own in traffic back-ups




Probably over-the-top but after a major engine job I change my oil and filter again before 500 miles and re-check head bolt torques(Cold engine and recommended .The filters are cheap as is the 15w40 diesel engine oil so why not treat the old girls nice




PS

Old engine oil can be mixed with creosote to make a really good fence paint/protection and or with car under-seal for a really good protective
 

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PS

Old engine oil can be mixed with creosote to make a really good fence paint/protection and or with car under-seal for a really good protective
shep my dad God love him,collected all the old engine oil,neighbours as well,painted every month the under side of his 1966 hillman minx,i was 6 then,and my first introduction to mechanics

oh if any one has one,i can explain how to split the ball joints.lol

 

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shep my dad God love him,collected all the old engine oil,neighbours as well,painted every month the under side of his 1966 hillmam minx,i was 6 then,and my first introduction to mechanics


We had a bond 3wheeler when I was an ankle biter and my Dad used to oil paint the chassis






We had a BSA with a Sidecar before that and used to go to the seaside in it
 
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