Speedometer inaccuracy

[C. Lee]

Good morning all,
When I had my 16 RTL I noticed that the speedometer was off by about 2mph at highway speed. I've just traded for a 19 RTL (see photo) and it has the same issue. Am I crazy or have you experienced this also? Is there any corrective action? Thanks for your help. Chris

 

[Freddy]

Only 2% at h/way speeds - what wrong with that? They're not capable of being precise. Even tyre inflation, wear and load would give a variation.

 

[spyder01]

That seems to be the norm for many RTs,but if you change rear tire to a car tire which has a slightly larger diameter it will be accurate.

 

[Spyder601]

I'm on my 3rd spyder and they have all been 2 mph over actual speed.

 

[Grandpot]

What are you comparing it to?

 

[Spyder601]

I’ve noticed it on radar guns on the interstate as well as my GPS and phone apps

 

[BLUEKNIGHT911]

That seems to be the norm for many RTs,but if you change rear tire to a car tire which has a slightly larger diameter it will be accurate.

Like a 215/60-15 size will make it almost exact ….. Even auto & pk-up trks are slightly optimistic …. this may be a Fed. Govt. rule ……. Mike hyea:

 

[h0gr1der]

I did notice this on my 2018 RTL. I think it is built in for some reason. On my previous bike, a Kawasaki Nomad 1600, it was much worse. On the Spyder, it appeared to me to be 2 MPH off at 70, but unlike many other bikes it wasn't truly a linear error. It was like they put a 2 MPH error in the software.

I installed a slightly larger diameter tire, a 205/60R15 car tire, and it corrected about half the error. I've read the 215/60R15 makes it read perfectly. I'm nit-picky, I would like my speedometer and miles to empty to be accurate, but they will never be.

If you do put larger tires on the back, while correcting the speedometer, it will push the odometer off. In my testing, I checked both the speedometer and odometer, and while the speedometer was originally 2 MPH off at 70, the odometer was pretty close to good.

 

[Lew L]

Speedo error fix

With a General Tire Altimax rear tire in the 215-60 -r15 size ----- the speedo is ONE mph from the GPS. Couldn't ask for any better. Every motorcycle I've ever owned was worse than that.

Lew L

 

[starrider60]

I rode Yamaha Road Stars for years and they were all at least 5 MPH off. I put the General Altimax on the rear of my 2017 RTS and now the indicated speed is only 1 MPH off :doorag:

 

[cruisinTX]

205/65 results in 0.5mph error at 75

 

[sandeejs]

Every motorcycle I ever owned was off. I assumed it was to make one think they were gong fast, therefore reducing the problem of motorcyclist speeding.
~Sandee~

 

[Pirate looks at --]

Who Cares!:roflblack:

 

[Freddy]

Who Cares!:roflblack:

Well, a dozen folks seem to. But I'm with you - same with fuel consumption and listing all the special do-dads attached to or hanging off my trike.

 

[Chupaca]

Here's the thing..

The only one you would need to compare yours with is the one the police are pointing at you.... and by then you will be owing the city some big bucks....:shocked: and most of them are off from yours and theirs as well....Considering this is the only adverse effect on you most law enforcement know this and do allow for some leaway....:thumbup:

 

[billybovine]

Almost all motor vehicles are made to have some error in the speedometer. I have not looked it up recently but I believe it is -0 to +10% is allowed. It appears manufacturers aim for +2%. This allows for tire changes and other factors.

Why is it that folks expect the Spyder speedometer to be extremely accurate? Yet their other vehicles are likely the same way and does not seem to be a problem.

 

[johnny canuck]

I have a 17 RTL. My speedo is off by 2-3 "KM"/hr. Doesn't effect anything. If you have a GPS that shows speed it will give the accurate reading. Running car tires at the same size as the OEM's. I'm not going to worry about it.

 

[ARtraveler]

Have had five :f_spider:'s now. They have all been 2 mph "slow" compared to standards. I use the "Your speed is X mph" signs as a guide that usually are seen at construction areas.

My Kawasaki MC's have always been about 5 mph less than what was shown on the speedo.

I usually do not try to compensate for the differences. We usually follow the traffic speed if there a lot of cars. If we have the road to ourselves, then I usually go posted plus 5 as a maximum. On nice scenic roads (when we have them to ourselves), sometimes will ride 10 mph LESS just to enjoy the scenery. I have not had a speeding ticket in over 20 years...and we roll through the speed traps all the time.

 

[bigbadbrucie]

I just can’t understand why so many people are so concerned about the speedo error on our Spyders. As a few others have stated, all of our vehicles have a speedo error. Your cars, your trucks, your bicycle....all of them, including your GPS. The GPS depends on how many different satellites it accesses on a given reading, so....how do you know for sure how much it is out? jmho wtfdik

 

[Grandpot]

No one will have a perfect speedometer. Police cars have "certified " speedometers. As good as they are, just slight difference in tire pressure will throw them off.