Why not 42 psi in the front vs 38psi in the back?
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Road Warrior
Joined: Jul 2012
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From: Ft Myers FL
Why not 42 psi in the front vs 38psi in the back?
As my title states...every HD mechanic tells me that the front of the bike is heavier then the back...so why not switch the tire pressure accordingly ???
Sine the front is heavier shouldn't the pressure be higher so that it somehow matches with the lighter end?
Sine the front is heavier shouldn't the pressure be higher so that it somehow matches with the lighter end?
Seasoned HDF Member
Joined: May 2012
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From: Carlsbad, CA
I don't know what the f/r weight ratio is. But, I'm betting the HD engineers know what they are doing.
Think of the tire pressure as pushing weight off the pavement. The higher the pressure, the less area of the tire required to displace that weight...which cooresponds to a smaller contact patch. So, I guess the tire pressure is optimizing rolling resistance, sidewall flex, contact patch and traction.
Think of the tire pressure as pushing weight off the pavement. The higher the pressure, the less area of the tire required to displace that weight...which cooresponds to a smaller contact patch. So, I guess the tire pressure is optimizing rolling resistance, sidewall flex, contact patch and traction.
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From: SW Ohio
You're mechanics are mistaken.
Club Member
Joined: Jun 2007
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From: Bedford UK
I don't know who these H-D mechs are, but IMHO they are all wrong! Find a local weighbridge and measure your bike to confirm, one way or the other. I don't believe there is a bike made which is heavier at the front than the rear.
As for tyre pressures, use your owners manual as a guide. If you change tyre brand check with their website for their recommended pressures and use them as a guide. In earlier times I routinely added a couple of psi to the front tyre of my bikes, but I'm older and more sedate these days, so don't give the front tyre as much hard work to do.
As for tyre pressures, use your owners manual as a guide. If you change tyre brand check with their website for their recommended pressures and use them as a guide. In earlier times I routinely added a couple of psi to the front tyre of my bikes, but I'm older and more sedate these days, so don't give the front tyre as much hard work to do.
Last edited by grbrown; Dec 6, 2017 at 05:10 AM.
Seasoned HDF Member
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From: SW Ohio
A 2018 Street Glide comes with:
A 130/60B19 61H front tire. The 61 is the load capacity which means it's capable of bearing 567 lbs.
The rear tire is a BW 180/65B16 81H. The 81 load capacity means it's capable bearing 1,019 pounds.
While I'm not a proponent of the using the rear brake only (low speed, tight cone type work excepted), the longer wheelbase and rearward weight distribution of HD motorcycles makes the rear brake a touch more effective than on a machine with a 50/50 distribution and shorter wheelbase.
This last part isn't a knock on your mechanic friends but if they don't know this, they aren't as knowledgeable as they should be. Always verify what they tell you.
A 130/60B19 61H front tire. The 61 is the load capacity which means it's capable of bearing 567 lbs.
The rear tire is a BW 180/65B16 81H. The 81 load capacity means it's capable bearing 1,019 pounds.
While I'm not a proponent of the using the rear brake only (low speed, tight cone type work excepted), the longer wheelbase and rearward weight distribution of HD motorcycles makes the rear brake a touch more effective than on a machine with a 50/50 distribution and shorter wheelbase.
This last part isn't a knock on your mechanic friends but if they don't know this, they aren't as knowledgeable as they should be. Always verify what they tell you.
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Road Warrior
Joined: Jul 2012
Posts: 1,521
Likes: 185
From: Ft Myers FL
But why are you running the reverse psi on your bike...? If the gauges were actually good at measuring.
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Seasoned HDF Member
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From: SW Ohio
Some tires respond (perform and wear) better with higher than recommended tire pressures; the Night Dragon is one. I won't speak for the guy but he may be a heavy/only front braker and the higher front pressure can prevent cupping. Lower pressures in front combined with heavy/frequent hard front braking causes the center ridge of the tire to fold inward toward the rim leaving the sides of the tread to provide braking (at this point the front wheel DOES support more than the rear). This creates scallops on either side of the center line of the tread and eventually can cause oscillation in the steering. The only real cure is to replace the tire and add pressure. I have salvaged cupped tires when I was poor by sanding the scallops, but it's not a true fix.
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Seasoned HDF Member
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From: Sandy Eggo's North County
Low pressure may contribute to scalloped rear tires also.
The cold pressure is dependant upon load.
While 10 guages may give 10 different readings, pick one and just go with it.
Remember, the pressure we see is only the difference between the internal tire/tube pressure, and the atomosperic pressure when/where measured.
The cold pressure is dependant upon load.
While 10 guages may give 10 different readings, pick one and just go with it.
Remember, the pressure we see is only the difference between the internal tire/tube pressure, and the atomosperic pressure when/where measured.
Seasoned HDF Member
Joined: Jan 2011
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From: Michigan 15 Minutes East Of Hell
Low pressure may contribute to scalloped rear tires also.
The cold pressure is dependant upon load.
While 10 guages may give 10 different readings, pick one and just go with it.
Remember, the pressure we see is only the difference between the internal tire/tube pressure, and the atomosperic pressure when/where measured.
The cold pressure is dependant upon load.
While 10 guages may give 10 different readings, pick one and just go with it.
Remember, the pressure we see is only the difference between the internal tire/tube pressure, and the atomosperic pressure when/where measured.
The cold pressure is dependent upon load.
While 10 gauges may give 10 different readings, pick one and just go with it.
Herein lies the most practical and logical response to a tire pressure posting in quite some time !
