[Turkeysandwich]

is 90 honestly not fast enough for you on a death machine?? these arent crotch rockets nor do they handle like one

 

[tvpierce]

is 90 honestly not fast enough for you on a death machine?? these arent crotch rockets nor do they handle like one

Mine was smooth as silk at 100+.

I wouldn't want to be carving corners on the CX at that speed... but in a straight line, it was rock solid.

 

[Sture]

Bike mag tests (from the era) that I´ve read, tell about true speeds of just under 170 kph (105 mph) up to 185 (Das Motorrad (Germany)). 185 would mean exceeding redline in fifth - in fact just over 10000. I´ve never seen that (or had the guts to try hard) but my black one (with a fullsize windscreen) once (windstill) let me see a bit more than 9000 (9400 or so) on the tacho in fifth and still had more... Ran out of guts.. Speedo just over 180 kph.



I don´t think of CX 500 as a totally steady bike at speed. Light waveing is what I expect to run into - and normally I don´t get disappointed...



Sture

 

[bandit]

in my opinion,anyone who pushes a 30 year old 500 motor close up to,or over,100 mph needs 2 things.....

1/a talking to

and

2/e bay

 

[The Accidental Mechanic]

Okay, so based on all the aforementioned talk of speeds and RPMS, on my 1978 CX500 I'm hitting about 5,850 RPM at 65mph, is that 'in spec', would you think?



Sometimes it feels a little 'sluggish' like it doesn't want to go above 65 mph at wide-open throttle, but other times I can get it up to, oh, 70 mph or so and still feel like I have some more 'room to grow' before I start having visions of the cam-chain bolt rattling out into the engine at speed and I back off, or a curve comes up...and I too can't imagine snapping into a curve with a bike as top-heavy as this one is; talk about high-siding!



Don't get me wrong: I love the bike; but are my readings right??



John

 

[Shep]

They sound fine to me.As for the sluggishness it could be carbs/plugs/Ignition.As you most likely know losing a few pounds would help a lot.I've got about a stone to lose as I always put some on in the Dark months.I'm around 190 but usually get down to 175 lbs for the season

And with fuel prices as they are,especially over here,every pound off is some more fuel in the tank

 

[The Accidental Mechanic]

What?? It's not a beer belly...it's an Investment!

I'm 6'1" and (last time I looked) 220lbs; so yeah, *I* might have something to do with it, but I doubt it...and I probably AM due for a plug cleaning...I'll start with the simple stuff first.



Yeah, I agree: I thoughtgas was expensive over Here until I saw what you guys are shelling out PER LITRE! It makes us sound like a bunch of whiny..well..Americans!

 

[King_Panther13]

I'm bumping this thread so I don't have to start another.



I've been playing with trying to figure out the top speed of my bike lately using the GPS on my cell phone. Seems to me like it doesn't want to go any faster than 96MPH.



Yesterday I was on a long, flat, straight road and decided to test top speed. I was tucked down, and was holding my throttle way open and in fifth gear of course the speedo was pegged out, but my RPMs stopped at 8000. They just wouldn't climb any higher. I tried doing this again several times, rolling on in fifth, or accelerating up in fourth. But when trying for top speed, it just won't rev any higher than 8000 RPMs in the fifth gear.



The bike also wants to idle a lot slower after riding at rather high speeds, usually if I'm riding it around 80 MPH for a while. On top of that, my 0-60 is only about 7 seconds. Feels like the clutch is slipping in first and second, but I may not be revving it enough.



I'm chasing other engine gremlins that are soon to be taken care of, but I wonder what the forum's take on this particular issue is. I've never heard of a bike being unable to surpass a certain RPM like that when doing a high speed run...so some explanation would be much obliged. Of course, I'm a noob to the mechanical aspects of bikes, but I asked a mechanic friend of mine and he as well said that he doesn't have a clue why it wouldn't rev past 8000, and that the idle getting slower as the engine got hotter was especially strange.



Oh, and at the very least, I don't think it should be blamed on fuel. I run 87 regular normally, but I found a gas station in the middle of nowhere that was selling 90 grade with NO ethanol. I noticed no performance changes, but my gas mileage increased a very good amount.

 

[cdyoung1985]

I always run premium, and have hit the redline in 5th several times, running iridium NGK's. I'm about 140 lbs or so. I don't know my 0-60 mph, but I know that I run 1/4 mile in 14.8-14.9 with saddle bags fully loaded with parts books, rain gear, work shoes, and luggage rack with trunk also fully loaded, was on the way home from work when I decided to hit the drag strip.



Your clutch shouldn't slip unless you're revving it high and dumping it, at the track I'll hit 6500 and dump it, laying on the tank to keep the front wheel down, for the most part, and it slips for a second, but when it grips, it GRIPS, but other than that, it shouldn't slip. You should be able to go from no throttle to full throttle any time with no slippage, if it does slip, either it just needs to be adjusted, or it's starting to go out.

 

[Allan]

First thing I would do is make sure when you are W.O.T. the carb throttle is actually wide open,,if the cable was not adjusted properly you may not be getting full throttle. Hold the grip wide open with the engine off, and see if you can move the linkage at the carb to open the butterflies more.

 

[King_Panther13]

Being new to engines, I'm unsure if the clutch is really slipping or if it's something else...but it's most noticeable when I'm giving it tons of gas, and it feels like it isn't "gripping" completely for the first second or so. I don't think I ever notice it while revving and not shifting gears, so it may not truly be clutch slippage. I can describe the feeling as "notchy" a lot of the times, even if I've already finished shifting and I'm not touching the clutch. Uncertain if it's related or not.



As for the throttle cable...good call. I'll check that. I do know that a moto-guru friend of mine who's ridden the bike said that the throttle is "way too sensitive...either you're engine braking, or you're accelerating, and that's why the bike is acting up in the twisties." He went on to say that he thinks it's to blame on the CV carbs, but I'm not too sure that they're supposed to be that "notchy."

 

[Allan]

The notchy feel could be a sign that the carbs need cleaning. From what you describe it seems like you have a dead spot when you are first accelerating. It could also be a sign of too much slack in the cable.



As for the clutch,,if it were slipping I would think you would be able to get full rpm,,but not full speed,,the motor would rev but the power would not be transferred to the drivetrain.

 

[King_Panther13]

Then what I'm experiencing probably isn't clutch slip.



I do feel like I have a dead spot from a stop...almost feels like the revs drop for a second, very similar to how the bike performed before I overhauled the ignition system. I also feel like I have a flat spot around the 5000 RPM area. I really bite my tongue when saying that, because i know that that's the red flag for a bad CDI...but I have an ignitech, tecoparts coils, rebuilt plug caps, and iridium plugs. When I say flat spot, I mean say I give it a certain amount of gas, and the RPMs will climb, but almost feel like they "catch" a bit around 5000, and I feel as if I have to give it more gas to accelerate out of the 5000 area. I'll think that I'm giving it enough gas to climb all the way to redline, but I'll end up cruising at 5000 for a bit before giving it more gas to "push" out of it, and then finally shifting.



Anyhow, I just adjusted my throttle play. It had maybe 3/4 of an inch or so of play. I think I reduced it to an eighth of an inch of play. I may have brought it to a bit less play than it's supposed to have, but I can always adjust it out again in the future. I was watching the butterfly, and it looks like the "push" cable isn't moving at all. When the throttle returns, the "push" cable just bunches up under the butterfly, rather than staying on it. I took off the throttle assembly, and pushed it by hand while giving it full throttle, and it didn't seem like it was inhibiting the butterfly from opening fully, so I just hooked it back up and left it alone.

 

[DanCX500]

The notchy feel could be a sign that the carbs need cleaning. From what you describe it seems like you have a dead spot when you are first accelerating. It could also be a sign of too much slack in the cable.



As for the clutch,,if it were slipping I would think you would be able to get full rpm,,but not full speed,,the motor would rev but the power would not be transferred to the drivetrain.

I need to take the time to pull my carbs (for the 3rd time) and make sure every hole is cleaned out to the size it should be (the first and second time I just made sure I got air/cleaner through them)! I get the same feeling at lower speeds.

 

[lt1]

I'm bumping this thread so I don't have to start another.



I've been playing with trying to figure out the top speed of my bike lately using the GPS on my cell phone. Seems to me like it doesn't want to go any faster than 96MPH.



Yesterday I was on a long, flat, straight road and decided to test top speed. I was tucked down, and was holding my throttle way open and in fifth gear of course the speedo was pegged out, but my RPMs stopped at 8000. They just wouldn't climb any higher. I tried doing this again several times, rolling on in fifth, or accelerating up in fourth. But when trying for top speed, it just won't rev any higher than 8000 RPMs in the fifth gear.

The bike also wants to idle a lot slower after riding at rather high speeds, usually if I'm riding it around 80 MPH for a while. On top of that, my 0-60 is only about 7 seconds. Feels like the clutch is slipping in first and second, but I may not be revving it enough.



I'm chasing other engine gremlins that are soon to be taken care of, but I wonder what the forum's take on this particular issue is. I've never heard of a bike being unable to surpass a certain RPM like that when doing a high speed run...so some explanation would be much obliged. Of course, I'm a noob to the mechanical aspects of bikes, but I asked a mechanic friend of mine and he as well said that he doesn't have a clue why it wouldn't rev past 8000, and that the idle getting slower as the engine got hotter was especially strange.

Oh, and at the very least, I don't think it should be blamed on fuel. I run 87 regular normally, but I found a gas station in the middle of nowhere that was selling 90 grade with NO ethanol. I noticed no performance changes, but my gas mileage increased a very good amount.

Hello, you hit top end. Unless you're saying that you can pull in the clutch in 5th gear & the engine still won't rev past 8k. When the mechanical, gravitational and aero resistance matches the horsepower produced, speed no longer increases. Regardless of the redline or the biggest number on the speedo.



It sounds like your mechanic friend is also "a noob to the mechanical aspects of bikes". An honest 96mph is not too far off on a well-used CX500. FWIW, most vehicles will not pull redline in top gear. Many newer vehicles have speed limiters, but there is no electronic speed limiter on the old CX/GL's. Just old-fashioned physics.

 

[ramprat06]

I agree with Allan's thoughts, but if you really expect this machine to perform in the manner you are trying, you likely will be disappointed overall. They weren't built for that. Not only that, but you mention you have other engine gremlins......if this motor is not perfect, the results won't be either.



Joel in the Couve.

 

[CXSarnia]

Well, straight out of the box, and 1000km break in period completed, added to the performance, the carbs that had been refurbished by Larry, and what do you get. Textbook 105 mph. GPS verified. 170.6 km/hrPretty much the same results I remember back in 1982. Changes in conditions compared to 1982... Me...gained about 80 lbs since then. Road..... slight down-hill, tail wind 5 knots - hugging the tank,with only a full face helmet for protection (no windshield)

 

[King_Panther13]

I don't expect the bike to be able to cruise at high speeds all of the time...I barely ever try to go that fast anyhow. I was just trying to see how fast it would go and what symptoms it would show to see if maybe the results would make diagnosing other gremlins any easier.

 

[DavidfromWisconsin]

My GL500I in full dress pulled 102 before the curves were coming. That was an honest 102 GPS speed.



It did get a little light on the front end, but I have some weak fork springs.



I remember weighing 220 ... when I was in college 40 years ago ... so that was a factor on why I didn't reach red line ...

 

[busdriver]

I have seen 99 mph on my gps with the normal fairing, bags, trunk and camping gear on my 1982 GL500I

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