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I was wondering what is the top speed of a GL 500i? I stay at the speed limit, to costly to get a ticket

Ev.
 

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My gps says I did 238 mph as my max. However I understand that the top speed is in the 105 mph range, since a cx will go 11 mph per 1000 rpm in top gear.



Mike
 

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Really? I guess its because of the gearing. I'm sure with different gearing I'm guessing they could probably hit 120 before wind resistance is too much for the rider/bike.
 

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Brand new, magazine reviews only got it to just above 100, I think the highest I saw in any review was 109.
 

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really only 109?? when i first got the bike it had a 120 speedo and i had it up to 115 (it was fun) now will i do it again nope......and also that was on flat land also with no wind so i dont know unless the speedo was off.....
 

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Approximately 105mph at Redline.

Bear in mind that unless your speedometer has been professionally calibrated, it is not accurate.

If your indicated is 110, actual speed is more likely in the 103-104mph range.
 

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ok so then i was roughly only going around 108 then??
 

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I thought gear driven speedo's were generally dead on. Is that descepancy because of the cable kinking about
 

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I've never had a bike with an accurate speedometer. They seem to all read fast. My current speedometer reads about 5 mph fast at 65 mph. I usually ride with a GPS and just use that speedometer. If you have the correct front tire the odometer of a gear driven speedometer can be very accurate. My odometer matches my GPS.
 

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I've never had a bike with an accurate speedometer. They seem to all read fast. My current speedometer reads about 5 mph fast at 65 mph. I usually ride with a GPS and just use that speedometer. If you have the correct front tire the odometer of a gear driven speedometer can be very accurate. My odometer matches my GPS.
 

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Apparently ALL motorcycle speedos are not accurate.



Never had one match my GPS, all showed faster by about 5-8 kph.



Just yesterday we were having this conversation at the local coffee shop, and one guy piped up



it was because of a liability issue on the mfgs. part. Did not get a chance to further the reasoning



of this because, a 1948 flathead Harley Davidson with sidecar pulled into the lot and the conversation



changed instantly. WOW what a showbike. Never made it back to the speedo topic.
 

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All speedometers are over and under at certain speeds. As for mechanical speedometers being correct well what's mechanical?



Sure a gear spins at the wheel and connects to a cable. But when it goes into the back of the speedometer that cable turns a turns a gear and a magnet. The gear goes to the odometer/tripmeter and the magnet pulls the needle into the right position but without resistance it is off. So to do that there is a spring inside. Over time springs lose tension and inaccuracy happens. Now we have another fail rate.



I can tell you that I test all my speedometers with a drill and set them to 64mph which is the speed the drill will turn them. Anything above or below is off.



I have one that's dead on at 64mph but at 30mph it thinks it's going 20. And that's not good.
 

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Down hill, with a tail wind, and only looking at a gps, I got my 'nearly new' GL500 engine to pump her up to 113 mph.

keep in mind, any additional equipment onboard will limit actual top speed (ie windshilds/saddlebags/trunks,

and large sized middle aged males) I seem to remember, back when the bike really was new, in 1982,

and I was still only about 116 lbs. soaking wet, I broke 120 on the speedo - best you could do

back then, as there weren't any gps devices.



As for why... I believe the 5-10 m/h over is built in to avoid Honda's liability of speeding tickets. If you ride the

limit, and the cop has his radar accurate - you are actually doing less than the speed limit, and will NOT

be receiving a ticket.
 

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The original owner of my CX got pulled doing 115 mph when it was fairly new. He had it just below the redline. When the trooper asked what he was doing he said "riding fast." Luckily for him he knew the guy, especially considering that was in the 55 days.
 

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FYI, one of the fellows in our group at Bonneville ran a stock appearing GL500 in Production Pushrod class. This bike has a 650 primary drive, mated to a 500 trans, 12.3:1 CP pistons, Webcam grind, GL650 valves, and Kemph ported heads. It also has the headers split and the inner tubing removed, then rewelded, plus a set of GL650 carbs. Density altitude on our time slips showed around 6000-7000 FT, and the rider weighs about 285. The bike would pull 11,000 RPM in the lower gears, but couldn't pull 5th gear.



The bike finally went 97mph on the salt....pretty good for the air density and rider weight! It is seriously hampered, for top speed, by the long intake and exhaust tuned lengths....it just WON'T come "on the cam" like my other engines do. We will try the bike with my carbs/manifolds and my exhaust lengths to see what happens at El Mirage (pretty similar air density, compared to Bonneville). I'll let you know if it works better.



Regards, JimL
 

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I'd be really interested to know how the magazines at the time measured the speed, as they all universally wrote that the CX topped out in 5th at 105 to 109.  I have one article that says the cx custom made it to 106 in 1/2 mile.  These articles were all for the 500's, I don't remember what the 650's top speeds were but I know they were about 2 seconds quicker to any speed.
 
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