rpms for a 1500


Information and questions on GL1500 Goldwings (1988-2000)
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Nlmman47
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rpms for a 1500

Post by Nlmman47 »



i have an 92 1500 that i am restoring. and i know from previous post that 3000 rpms for 70 rpms is normal. and thats what my 93 goldwing runs at. but i took my 92 on the open road and at 70 mph i was running at @ 26 2800 rpms lot smother ride. and the motor is running smother, not that i am complaining but why, what is it doing that my 93 is not. i know that my 93 has 30000 more miles on it but i am curios why and if i can make the adjustment on my 93. i recently rebuilt the petcock on the 92. also i notice since i rebuilt the petcock. to start the bike even after it warm up i have to open the throttle a little to to crank it up?


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Rambozo
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Re: rpms for a 1500

Post by Rambozo »

Did you get the speed from a GPS? The 1500 has a notoriously flakey speedometer.
Do you have the same size tires?
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

no just check against speedometer. but keeping with traffic. but i will have to check speedometer. front same size different profile. it looks more flat looking than round
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

but it has better pickup than my 93. and rounds quitter
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Rambozo
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Re: rpms for a 1500

Post by Rambozo »

Nlmman47 wrote: Mon May 13, 2024 9:45 am rounds quitter
??? :?: :?: :?: ???
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

A wheel with a higher bead than the original gives you less RPM at the same speed.
At night and at 100 it is not noticeable.
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Re: rpms for a 1500

Post by blupupher »

what size rear tire is on each bike?
Tire condition of each?
Current ride: 2013 BMW K1600GT

Former rides: 2002 GL1800A, 2001 CB750, 1994 GL1500 SE, 1994 VT1100C , 1984 VF500F, 1982 CB750C, 1982 GS250T, 1981 CB900C, 1978 CB125s, 1976 TS185
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

i have to check the front tire size not sure what it is. the back tires on both are new little wear. and are you talking about the bead size on the front tire?? the back tires are factory sizes.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

also has any one have and ideal on why i have to open throttle a little to crank the bike. does it have anything to do with the recent petcock rebuil?
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

The engine should start with just the choke and a touch of the start button, nothing more.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

i did check the front tire size and it is a 130 / 70/18
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

Well, that's right. The rear tire is 160/80/16 unless you are on the dark side.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

back tire is new and the correct size
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Re: rpms for a 1500

Post by paseandoconhonda »

Well, I would have to check the tachometer cables, I have a problem with it, it reads more RPM than the engine actually goes, for example at 80 MPH it reads 5000 RPM, but the engine sounds normal, obviously it is reading wrong, check cables and chips, I just need to remove the dashboard, but I decided not to do it for now so I directly chose to ignore what the tachometer shows and that's it. Maybe something similar is happening to you. And I clarify, it is not the clutch, it does not slip nor does it have power problems when accelerating, it is simply a wrong reading who knows why.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

i understand, i have to verify my speed but the engine does not sound like its running at 3000 rpms. it sounds smoother like it reading correctly and if it is and at the speed of 70 then thats good. but it makes me curious why my 93 runs higher rpms. if one can so can another. but i dont have high hopes. but it would be nice. maybe someone before me change the rear drive gears out. but i will check and verify my speed
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

It could also be that the speedometer is reading incorrectly, perhaps it is a good idea to check with a GPS how much difference there is and if it is really going at the speed it says it is going.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

I check my speed using gps, and it shows about 5 mph more than what gps says. But at 70mph according to gps the rpms is still at 26 to 28 rms
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

Generally and due to global regulations, vehicle speedometers will always indicate more than what you are actually going, the percentage depends on each country or continent. So if the speedometer reads 55 mph, the GPS would have to read around 50 or 52. That said, if it's the other way around, something is wrong. Anyway, 70 mph and 2800 RPM is a bit low. I leave you a photo as an example of how it should work. Anyway, I don't see a problem there, I don't know about you.
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At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

I understand what you are saying. But I took my 93 goldwing out and check it the same way and it was close to what the gps ways saying. My 93 at 70 mph the rpms run 3200. It just seems weird
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paseandoconhonda
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Re: rpms for a 1500

Post by paseandoconhonda »

Before you said 2600 to 2800 RPM at 70 mph, that's a little low, but now you say 3200, that's closer to being correct.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

Sorry for the miss understanding. I have a 93 goldwing to. It my daily driver. The 92 is the one I'm restoring
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Re: rpms for a 1500

Post by FM-USA »

Several thousand miles ago I replaced the speedo cable. IF memory serves there was a difference in speed reading, newer cable was showing faster speed at the same 3k RPMs. How much, off hand not sure, guess would be 3-ish mph..

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Re: rpms for a 1500

Post by paseandoconhonda »

Now I understand, you have 2 GL, well, then that's what I told you before, at 70 mph 2800 RPM is not enough, something is not right there.
At night and at 100 it is not noticeable.
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Nlmman47
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Re: rpms for a 1500

Post by Nlmman47 »

yes i agree, but if the speed is right, the only thing i can think of is some previous owner put a different gear in the rear to make it do that. which would be great. but noway to find that out. but it runs real well and has great pickup which again makes me thank of new gear
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Re: rpms for a 1500

Post by Rambozo »

AFAIK Henry's drive gears are only for the 1800.
It's easy to measure your final drive ratio. Just pull back the u-joint boot, and mark the rear wheel and turn it, noting the shaft rotations for one turn of the wheel.


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