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vito1943
07-24-2021, 07:52 AM
When riding two wheels I always preferred to inflate my tires a bit on the high side, and now on the Spyder I do the same. Plus I want to keep the number of times that I have to add air to the rear tire down to as few as I can. I bought a TPMS system, and inflated the rear to 30, not the recommended 28, and the fronts to 22, not the recommended 20. These are cold temps so obviously the pressure will go higher after riding a bit. Is this too much to be safe?

Peter Aawen
07-24-2021, 08:10 AM
The more over your tire's optimum pressure that you run them at, the less they'll be likely to increase in temp/pressure as you ryde; but they'll also have less real traction, be more susceptible to punctures from road hazards/debris etc, wear quicker, and give you a harsher ryde. :lecturef_smilie:

That said, unlike the higher load & speed rated Passenger Car tires that many run safely & successfully at lower pressures, the lightly constructed OE Spec Kendas really NEED the BRP/Kenda recommended pressures to function at all reasonably &/or safely, so running them at 22/30 psi instead of the recommended 20/28 psi is really only over-inflating them juuust a little, so none of those things are probably going to be too much worse than they are anyway - except maybe for the rapid wear rate, especially in the centre of the rear tire's tread! :rolleyes:

Good Luck! :cheers:

BajaRon
07-24-2021, 09:15 AM
Over inflation on the front tires with the stock Kenda's can make steering twitchy. The Kenda's tend to roll under on hard cornering (Fronts). Over inflation will reduce that effect somewhat. Of course that ride will be harsher, as already mentioned. At recommended pressures, the rear tire has about a 2.5-3" contact patch with the roadway at speed. Additional inflation will reduce this contact patch size. And, as mentioned, will increase the rate of wear, which is already quite poor. Many reduce the air pressure in the rear tire in an attempt to increase the contact patch and mileage.

As always, everything is a trade-off.

vito1943
07-24-2021, 10:54 AM
So far the handling and riding with the pressures that I have seems fine. I've put on 1,000 miles now in the almost four weeks that I have owned the Spyder.

BajaRon
07-24-2021, 11:04 AM
So far the handling and riding with the pressures that I have seems fine. I've put on 1,000 miles now in the almost four weeks that I have owned the Spyder.

It may be a case of you don't know what you don't know. If you're curious. Drop the fronts to 18 psi and the rear to 26 psi. It isn't going to hurt anything or be dangerous. But it should be enough of a pressure change to make a noticeable difference. Then you will have something to compare to.

RICZ
07-24-2021, 11:37 AM
Although I have switched to car tires on the front, I still have the original Kenda On the rear. When riding a twisty road aggressively, the rider behind me says it looks as though the rear tire is trying to roll of the rim. Yes, it is at 28 psi.

Mikey
07-24-2021, 11:51 AM
:popcorn:

BajaRon
07-24-2021, 12:07 PM
Although I have switched to car tires on the front, I still have the original Kenda On the rear. When riding a twisty road aggressively, the rider behind me says it looks as though the rear tire is trying to roll of the rim. Yes, it is at 28 psi.

That following rider is correct. The fronts are worse than the rear. More pressure improves this. But I am not sure it makes that much differents at any reasonable pressure. I think the loss in tread compliance (thus traction) may negate much of the handling improvement achieved with increased PSI for tire roll reduction.

The reports I am getting from the new Kanines compared to the OEM Kendas are that tire roll is much improved. I will be trying them myself once I can get my hands on a set long enough to put them on my Spyder. There is no doubt that the Kanines are much improved over the OEM Kendas. But frankly, a well made rubber band would probably work better. In other words, a very low hurdle.

The questions now left to answer address how the new Kanines compare to car tires. Just based on the difference in purpose and format, I think we can expect better traction, similar handling characterizes, shorter life span (again, how much to be determined) and probably softer ride.

The job of the curious is never done!

Mikey
07-24-2021, 12:26 PM
:popcorn: You guy's just keep on beating the brush, and reporting the good and bad news, because sooner or later I am going to need tires and need the FULL scoop of what's hot and what's a flop!!!:spyder:

BLUEKNIGHT911
07-24-2021, 03:28 PM
Although I have switched to car tires on the front, I still have the original Kenda On the rear. When riding a twisty road aggressively, the rider behind me says it looks as though the rear tire is trying to roll of the rim. Yes, it is at 28 psi.

That's because the " casing " is weakly made compared to Auto tires .... I have ( accidently ) let my rear Michelin tire get down to 8 lbs. PSI, yes it was a bit squirrely but really not to bad ... and at the Drags in Missouri I had the rear at 12 lbs. ....... I wouldn't dream of doing that with a Crapenda :gaah:..... Mike :thumbup:

CHUCK1
07-24-2021, 07:55 PM
Thinking of replacing rear with altimax rt43 but since can not find 225/50/15 standard size what is the best size to replace stock. Also is this the best tire chose at this time.

BLUEKNIGHT911
07-24-2021, 10:40 PM
Thinking of replacing rear with altimax rt43 but since can not find 225/50/15 standard size what is the best size to replace stock. Also is this the best tire chose at this time.

The Altimax RT43 is available in 215/60-15 ..... and this will make your speedometer read almpost perfect ... compared to the OEM 225/50-15 .... 100's ( maybe 1000's ) of folks here use that size ..... Mike :thumbup:

CHUCK1
07-25-2021, 08:19 AM
thanks for your input

Mazo EMS2
07-25-2021, 11:17 AM
A couple of pounds over isn't a deal breaker...but most here prefer the ride of under inflated tires. I think for the most part folks prefer the ride quality over worrying about the life of tires and such

vito1943
07-25-2021, 12:08 PM
When I convince myself to crawl back under the Spyder to get to the rear tire I might let out some air and try lower pressures, but for now I think I will stay off the ground. With my prosthetic knees I cannot kneel on the ground, and with my damaged shoulders I am limited as well. Riding is no problem, getting to the tire valve in the rear is a real PITA for me.

BLUEKNIGHT911
07-25-2021, 12:20 PM
A couple of pounds over isn't a deal breaker...but most here prefer the ride of under inflated tires. I think for the most part folks prefer the ride quality over worrying about the life of tires and such

Neither Peter nor I recommend or even suggest anyone ride on " Under-inflated tires ", that's dangerous. .... What we advise to all is to use a PSI commensurate with the WEIGHT of the LOAD. .... when folks started using Auto tires on Spyders, we figured out what PSI should be used on a much more robustly constructed tire compared to a Crapenda !!! .... the PSI numbers were arrived at buy using Tire Science, as opposed to Butt Feelings ...... Mike :thumbup:

2dogs
07-25-2021, 12:37 PM
When I convince myself to crawl back under the Spyder to get to the rear tire I might let out some air and try lower pressures, but for now I think I will stay off the ground. With my prosthetic knees I cannot kneel on the ground, and with my damaged shoulders I am limited as well. Riding is no problem, getting to the tire valve in the rear is a real PITA for me.


:gaah: :agree:

BryanSD
07-25-2021, 02:08 PM
When riding two wheels I always preferred to inflate my tires a bit on the high side, and now on the Spyder I do the same. Plus I want to keep the number of times that I have to add air to the rear tire down to as few as I can. I bought a TPMS system, and inflated the rear to 30, not the recommended 28, and the fronts to 22, not the recommended 20. These are cold temps so obviously the pressure will go higher after riding a bit. Is this too much to be safe?

For what it's worth, the service department at my dealer brought up that the Kenda's seems to wear a lot quicker when overinflated (30 lbs vs 28 lbs likely isn't his definition of over-inflation). Anyway he encouraged me to stick at 28 lbs or go just a little under...but never overinflate. On a side note, I put on the Kenda Kanine KR20 tires and I'm much happier with them than I was with the original Kenda tires. I was in a freaking rainstorm in the Black Hills at 55 MPH, handled the curves well, and never hydro-plane. Some other Spyder riders weren't so lucky.

T.P.
07-25-2021, 03:14 PM
On the tire loading sticker in the frunk on my 2017 F3T it says for the oem Kenda tire, 15+2 psi for the fronts and 28+2 psi for the rear.

On the tire loading sticker in the frunk of MRS.T.P's 2020 F3L it says for the oem Kenda tire 15psi for the fronts and 28psi for the rear.

Where are people getting the 20-22 psi recommendation for the front Kenda's ?

I'm close to two years running the Quatrac 5's on mine and MRS.T.P. has just been switched to the new Quatrac tires.

T.P.

Peteoz
07-25-2021, 04:29 PM
My ‘21 RT sticker says 20psi front, 28psi rear, T.P. :thumbup:

Pete


On the tire loading sticker in the frunk on my 2017 F3T it says for the oem Kenda tire, 15+2 psi for the fronts and 28+2 psi for the rear.
On the tire loading sticker in the frunk of MRS.T.P's 2020 F3L it says for the oem Kenda tire 15psi for the fronts and 28psi for the rear.
Where are people getting the 20-22 psi recommendation for the front Kenda's ?
I'm close to two years running the Quatrac 5's on mine and MRS.T.P. has just been switched to the new Quatrac tires.
T.P.

BLUEKNIGHT911
07-25-2021, 04:33 PM
On the tire loading sticker in the frunk on my 2017 F3T it says for the oem Kenda tire, 15+2 psi for the fronts and 28+2 psi for the rear.

On the tire loading sticker in the frunk of MRS.T.P's 2020 F3L it says for the oem Kenda tire 15psi for the fronts and 28psi for the rear.

Where are people getting the 20-22 psi recommendation for the front Kenda's ?

I'm close to two years running the Quatrac 5's on mine and MRS.T.P. has just been switched to the new Quatrac tires.

T.P.

I HOPE your not using Crapenda PSI's on those Q-5's..... if so they are way overt-inflated ..... Mike :thumbup:

Peteoz
07-25-2021, 04:35 PM
Vito, have you considered looking at FOBO? It’s a right pain for me to get at the rear valve also, but FOBO means I only have to do something when the pressure is actually low, and it is an easy phone check of tyre pressures before every ride. If I do have to add air, I use a low mechanics stool to sit on, and if you roll the Spyder so the valve is at around 3 o‘clock you can reach the valve without stressing those knees:thumbup:…….although, I don’t have bad shoulders to contend with, like you :dontknow:

Pete


When I convince myself to crawl back under the Spyder to get to the rear tire I might let out some air and try lower pressures, but for now I think I will stay off the ground. With my prosthetic knees I cannot kneel on the ground, and with my damaged shoulders I am limited as well. Riding is no problem, getting to the tire valve in the rear is a real PITA for me.

2dogs
07-25-2021, 05:58 PM
When I convince myself to crawl back under the Spyder to get to the rear tire I might let out some air and try lower pressures, but for now I think I will stay off the ground. With my prosthetic knees I cannot kneel on the ground, and with my damaged shoulders I am limited as well. Riding is no problem, getting to the tire valve in the rear is a real PITA for me.

I have an inexpensive digital gauge that is quite close to what my FOBO's readout. I've gone through several gauges that vary in their readouts of as much as 4lbs. I don't fight with putting pictures on this sight, but I use an air chuck that's used by truckers to air up duel tires. It's a double-headed air chuck. Very common air chuck. It's just the right angle to air up the rear tire without being on your knees or standing on your head. I do exactly as PETEOZ does and it works well for me. I've discovered that my FOBO's are actually worth twice what I paid for them. I carry one of those air chucks in my spyder with all three types of air hose connectors, so if I have to air up when I get gas or whatever, I can connect to just about any air hose out there.

Peteoz
07-25-2021, 10:48 PM
Yeah, I really should get one of those double-headed chucks, 2dogs. Thanks. I rely on a rechargeable battery powered unit, and sooner or later, undoubtedly when I really need it, it is bound to let me down.:lecturef_smilie:

Pete

2dogs
07-25-2021, 11:28 PM
Yeah, I really should get one of those double-headed chucks, 2dogs. Thanks. I rely on a rechargeable battery powered unit, and sooner or later, undoubtedly when I really need it, it is bound to let me down.:lecturef_smilie:

Pete

Yea I think like that too and it usually happens. So, don't think like that.