High psi in a rear on the front.

[JaysGone]

Guys
I need a little bit of wisdom here.
There is a slight discussion going on elsewhere in regards to trikes.
With most who use a rear on the front running it at 41psi the max psi for a 130 MPA rear tire.
Me of course being me, and only having maybe 250K miles of Darksiding under my belt on 2 wheels.
But only a few thousand on 3.

Id like some of your opinions on why I should run a rear on the front at max psi.
Since no one has written a book on this yet and its not written in stone anywhere.
Aside from the most obvious problem being cupping.
Id like to hear why some of you do what you do.

Please guys Im not looking for an argument nor my being a negative Nelly on this.
Id just like some rational reasoning why a lot of you run it so high or not, in your opinions.
I would like some opinions since my reasoning on 2 wheels might not apply to 3.
Im a novice here with 3 wheels.
Only 15K in my 1st year with the trike.
Im just looking for opinions guys, nothing more.
Thanks
Jay

 

[suvcw04]

From what I have read, running a rear tire AND running it at high pressure, keeps the sidewall flex to a minimum. That flex would add steering inputs that you do not want.

 

[SMSgt]

Well Jay since you asked I'll give you my opinion. First running it backwards is because the rear tire is designed to give it's best performance upon acceleration, right? And on a trike you don't need that anymore because you have one or two larger tires doing that work for you now.
When you apply the brakes most of the stopping force is applied on the front wheel, somewhere in the neighborhood of 80% or slightly more. Now that didn't change just because you added an extra wheel in the back, all that weight still transfers forward. By putting it on running in reverse you have put the pressures the same but opposite on the front wheel. Instead of the pushing pressure to make the bike more you are using the exact same pressures, as far as the tire knows, by applying the brakes. Does that make sense.
Now the 41 PSI you are applying a much greater side force to your front tire in turns now than you ever do on two wheels because there is so much centrifugal force pushing you outward. You aren't leaning into the corners anymore and your wheel is staying up straight. So 41 PSI will keep the side roll out of your front tire and keep you more in control.
Now the next thing you do is buy yourself a good quality fork brace, if you don't already have one. You won't regret it.
That's my 2 cents worth.

 

[jaxbobg]

Thanks SMSgt,
That's about the best explanation I've ever seen in the hundreds of threads about running rear tires on the front wheel of a trike.

I was really into your mojo until the last sentence of your missive. Why would a trike need a special fork brace?

I'm pretty sure that my LT is already stabilized by the design of the forks themselves. Not really sure if that's a BMW design or if the Hannigan engineers took care of it when the conversion was done.

 

[Gold Rush]

The primary reason for higher pressure is, as mentioned already, to reduce side wall flex. You'll never eliminate it but anything we can do is wise.... Reducing the flex slows down the cupping and really makes steering dynamics more manageable.

The down side to higher air pressure is harsher ride and maybe a bit more ware on the suspension. Guess it's a trade off. :xszpv:

 

[msrvpeig]

I agree with everything SMSgt said, until he gets to the part about the superbrace.

I have an '05 Goldwing/Motor Trike with 97,000 miles. I have had 2 MPAs, each got well over 20k and were mounted backwards. I also tried a BT45 mounted in reverse with a super brace. The MPAs both had minor cupping, but the BT45 had severe cupping and was worn out at 17k. Note, both MPAs could have gotten close to 30k, but I replaced them both times prior to leaving on long trips. I currently have an Elite3 radial on the front and it's pretty well shot with about 13k.
Now, for the ride. The BT45 with the brace was the most comfortable ride. But, riding somewhat aggressively in any twistys I came across, you could almost see the tire cup. The front was so stiff with the brace that the frontend would "push", to use a NASCAR term.
I did not like the ride of the Elite 3 radial, as it would at times feel like the front tire was rolling over on its side when cornering.
I will be buying a new front tire over the Winter, and I think I will go with the BT45 without the superbrace.

 

[Calgary]

msrvpeig

What do you use to balance your front tires and how much air pressure do you run?

 

[Jenkinsrawhide]

I agree with everything SMSgt said, until he gets to the part about the superbrace.

I have an '05 Goldwing/Motor Trike with 97,000 miles. I have had 2 MPAs, each got well over 20k and were mounted backwards. I also tried a BT45 mounted in reverse with a super brace. The MPAs both had minor cupping, but the BT45 had severe cupping and was worn out at 17k. Note, both MPAs could have gotten close to 30k, but I replaced them both times prior to leaving on long trips. I currently have an Elite3 radial on the front and it's pretty well shot with about 13k.
Now, for the ride. The BT45 with the brace was the most comfortable ride. But, riding somewhat aggressively in any twistys I came across, you could almost see the tire cup. The front was so stiff with the brace that the frontend would "push", to use a NASCAR term.
I did not like the ride of the Elite 3 radial, as it would at times feel like the front tire was rolling over on its side when cornering.
I will be buying a new front tire over the Winter, and I think I will go with the BT45 without the superbrace.

I watched the trike forums for over two years and that caused me to pick the Battleaxe 45 which I now have on but have not ran it long. The MPA
was a great high mileage tire but it sings.

 

[msrvpeig]

msrvpeig

What do you use to balance your front tires and how much air pressure do you run?

First MPA was old fashioned balancing weights, all the rest were/are balancing beads. All tires were at 41 lbs.

 

[jaxbobg]

Thanks Terry, you confirmed what I suspected about the impact of the superbrace.
I'm considering the Battlax BT45 for my next front tire when I replace the current Metzeler.
Personally, I don't see the great love affair with the MPA. Is this just a Honda rider phenom?

 

[msrvpeig]

Thanks Terry, you confirmed what I suspected about the impact of the superbrace.
I'm considering the Battlax BT45 for my next front tire when I replace the current Metzeler.
Personally, I don't see the great love affair with the MPA. Is this just a Honda rider phenom?

To me, the difference in ride between the MPA and the BT45 is minimal. I experienced a "buzzing" or slight tingling in the hand grips with the MPAs when mounted in reverse. I did not experience that feel with the BT45. That's the reason I'm going back to the BT45 this Winter.

 

[jaxbobg]

Good to know. Appreciate your input.

(Now where in the #&%@ is that little button Zook provided to tell posters that you like their message?)

 

[JaysGone]

The primary reason for higher pressure is, as mentioned already, to reduce side wall flex. You'll never eliminate it but anything we can do is wise.... Reducing the flex slows down the cupping and really makes steering dynamics more manageable.

The down side to higher air pressure is harsher ride and maybe a bit more ware on the suspension. Guess it's a trade off. :xszpv:

Your down side remarks is exactly what I wanted to hear.
Im not at all concerned with cupping.
Personally Ive not had any handling issues at the pressure I do run it at but so far Im seeing what Ive asked for.
Thanks

 

[pcombe]

I run a rear tire on the front of my trike that is exactly the same size as my original front tire.( with the rotation backward)

#1 reason i run it at max inflation is that it handles better.
#2 reason is that doesn't react so bad when a side wind hits me.
#3 reason is i get less head shake.

#1 drawback is that the rubber is a harder compound than the original front tire and i can feel it hit a little harder on a bump but it is not a reason i wouldn't run the tire.


How DAT? :Coffee:

 

[JaysGone]

Ok so the consciences of the replies so far is running the tire at 41 psi is mainly to reduce flexing.

I should mention when I got the trike. It came with a new MPA rear mounted backwards.
Im guessing as there are no visible weights on it.
That it has beads.
@41psi.

On my 2 wheelers. All Darksided.
Ive used over the years Metzlers, Dunlops, Bridgetones and Kenda.
Never had issues with any of them. Most replaced at about the 10-12K mark.
All run at 30-34 psi.
The only tire Ive ever had cup was the OEM POS Slipstone regular front that came on the Yamaha.
I tossed that tire at 8K running it at 36 psi. Currently on it is a Kenda Cruz rear @30psi actually for the $$ a pretty good tire. With 10K on it and in good shape.

On the trike for the past year.
Ive tried running the MPA at 36psi for a softer ride.
At 41 as has been pointed out a pretty rough ride by my standards.
41psi cold warmed up had been in the 44psi range.
So I backed off.
Set at 36 psi cold it gets to about 39 warmed up.
Truthfully Id like to lower it a few pounds more.
I did add I guess because I could a Super Brace that to me has had zero affect + or -.

So far for me.
Almost 15K miles at 36psi and still have quite a bit of tread to go. No cupping no harsh ride, no negatives. Id like to try it a bit lower and if it kills the tire so be it.
But.
I now have flexing on the brain and maybe shouldn't do it.
I might also mention most fronts on my 2 wheelers are at 30-32psi, also with zero issues, worn out in the 10K range.

You guys have told me what I wanted to read and why and I appreciate it.
It seems to me the MPA is for whatever reason a Honda thing.
It would not have been my first choice.
When I do replace it it will be with a BattleAxe as of all that Ive used on my bikes.
Its been the best all around tire for me.

I have a funny feeling my riding style. Slow and steady never in a hurry. 99% flat straight roads commuting daily <BORING> is why I have no issues.
All the roads down here happen to be in the best shape of any area Ive ever lived in.
Well maintained, resurfaced it seems every 3-4 years on I-95. That includes local state roads redone 2X in 7 years so far. All smooth as glass, cant find bumps even when Im looking for them in my local riding area. City of Delray roads are about the worst and they aren't bad.
So for now I wont change anything but you guys have given me something to think about for the future.
Thanks All.

 

[jaxbobg]

Wow! JaysGone post is perched on the edge of poetry in some beautiful archaic pentameter.
A few more tokes and I could zone out for hours just contemplating the universe :LordHelp:

So, I guess you're saying that you've run all of your front tires below 35 psi all this time. Seems kind of soft to me, but hey, if that gives you the ride you like, so be it. Personally, I've never had less than 40 psi in my trikes' front wheel and never noticed that the ride was harsh or particularly jumpy.

 

[Veritas44]

Here's the Deal...
First and Foremost, you CANNOT equate ANY 2-Wheel Dynamics to Trikes when it comes to tires. You CAN'T. Not and be anywhere near "correct". Unless you deny the Laws of Physics and Engineering. Until you accept that FACT, you need to forget learning anything.
When one asks for "Advice" or Opinions based on experiences, one must be honestly and sincerely prepared to listen to those more knowledgeable and experienced and accept what is given.
Otherwise,,, you are just looking for Co-Signers to preconceived conclusions regardless of their validity or truth.

Never ceases to amaze how some ask for assistance/help/advice/direction then,,, want to debate and "poo-poo" what they receive when it doesn't jive with what they already concluded or isn't what they hoped to hear.

But hey,,, if that's Your Deal? Knock yourself out I suppose. Only thing is, sooner or later the ones who know the answers to the questions won't waste time in participating in the exercise in futility and frustration.

On this one, You asked the same thing on 2 Forums and received the same answer from a multitude of very knowledgeable and experienced TRIKERS with varying depth of explanation and proof......

 

[jaxbobg]

Veritas, you are truly the voice of reason!

Hundreds (perhaps thousands) of trikers have weighed in on this topic over the years.
40 to 42 psi is the accepted front tire pressure on a trike, regardless of the brand name.

 

[bikerbillone]

41 psi on a BT 45 <rear> with RideOn for balance and reducing the 'flat tire' syndrome on the the road. Just my use and opinion, others may disagree, but that's OK.

 

[MDGeorge]

There is one thing I would like to add to the mix.
I totally agree that the weight being forced onto the front when turning and stopping asks for a stiffer front tire.
A few months ago I added two inch fork lifters. It raised the front end so that it is level, rather than the front being lower than the bike.
Before the fork lifters, the bike was leaning into the front end. Lots of weight on the front tire.
Now, There is less weight and is very noticeable in the way the bike handles corners. It even makes a difference in how I sit on the bike. I am no longer leaning forward. I can back off the 41psi on the front tire and get a softer ride.
I am at 38psi now.