81 GS550 - Question about new tires (Not another tubeless debate)

[SunsetTwist]

Hey there,

Got this bike a few months ago, recently got it running now trying to figure out tires.

One thing that's really throwing me off is the fact that the PO has a tubeless on the front and a tube type on the rear. Additionally the rear tire is actually marked as a "front tire" on the sidewall and the direction of rotation is backwards. The fact that its designated as a front tire isn't too alarming (i think) but i mean come on, there's an arrow pointing it in the right direction!! Smdh at the PO... Anyone wanna chime in with their two cents on this please? Really just trying not to make a costly mistake with either my money or my safety on this one. Thank you!

Also if anyone knows a compatible set they could recommend that would be pretty awesome too.

Current setup
Front: IRC Duro Tour RS-310F 100/90/19 (TUBELESS)
Rear: Metzler ME 880 Marathon 120/90/17 (Designated as FRONT TUBE TYPE)

 

[Steve]

OK, here is my two cents, but I expect change.

Before saying anything about the tires, take a look at the date codes on the tires. If they are more than about four years old, they need to be changed regardless, so what is on there doesn't really matter. To read the date code, look for the DOT marking on the sidewall. Look at the last three or four digits, which should be in a separate stamping. Hopefully it's a four-digit number. If it's only three digits, don't even trust the tires to push the bike across the floor in the garage. If it's four digits, the first two digits are the week number, the last two digits are the year. A code of 3714 would be the 37th week of 2014, or about the last week of September.

Now, ... your front tire is one of the cheapest tires available. That alone does not disqualify it, as one of the very decent tires available is also among the least expensive. It's not necessarily the best VALUE, but still a decent tire. The size of your front tire is OK. I think the stock tire would be a 90/90. The 100 would slow down the steering feel a bit, but it also removes most of the typical speedometer error. Whether it should be tubeless or not depends on the presence of a stamping on the front wheel that says it can be used tubeless. Most tires available today can be run either way.

Your rear tire is supposedly one of the better tires available, but many have reported problems with tread blocks separating from the carcass. There is no immediate air loss, but it certainly reduces the protection over that area of the carcass and would certainly make it ride strangely. Some tires can be run either front or rear and are usually marked as such. They will show TWO rotation arrows, saying "For front tire use, mount this way <--" and "For rear tire use, mount this way -->". Again, tube vs tubeless would depend on the presence of a stamping on the wheel.

Also note that for a couple of years during the transition from tube to tubeless, Suzuki used a mixture on the same bike. Many bikes used a tube-type wheel on one end and a tubeless-type wheel on the other.

The "inexpensive, but decent" tire I mentioned earlier is a Shinko. Two models are commonly used here, the 712 and the 230. A pair of tires in either model is about $135, delivered to your door. If you don't feel qualified to change your own tires, you might find a local shop that carries them, or can order them for you, then install them. Most shops will charge a modest fee ($20-30 each) for mount and balance if you bring just the wheels. Some shops will do the job if you bring the entire bike, but be prepared to pay $75-100 PER WHEEL for the convenience. As you can see, the investment of a few dollars for some tire levers will save you a BUNCH of money.

.

 

[Reddog78]

The directional arrow is a function of the tire's construction. The front tire receives the majority braking force, while the rear sees most of the acceleration pressures. Braking and acceleration are opposite forces. Thus, the tire marked Front mounted backward on the rear makes sense. That being said, on my bike I would only mount a "Front" tire on the front.

I'm also in favor of mounting the tires yourself.

 

[Gorminrider]

Additionally the rear tire is actually marked as a "front tire" on the sidewall and the direction of rotation is backwards.

In your case, I think someone has extrapolated from the fact that the particular tires that can be run front or rear ARE reversed as to direction.... Avon Roadriders are an example of "reversible" tires.

I think this is(or was!) a common extrapolation where a perfect tire fit was not easily available . Nowadays, there's the internet and it's really much easier to source stuff from around the world PLUS it's easier for everyone to Know Everything ie: too much?

So, sifting through, it's just distilled to what the people that make the tire say-if the manufacturer says its ok, Otherwise, I wouldn't like to do it except in a real pinch .on the other hand, for you, now,.trundling down the road with decent tread can be enough if they're not going to come off.....and, I don't know of any Reversible tires that are expected to be Ultra anyways..

One other thing- not sure about your metzler? but tire sets can be very different in tread, front and rear... the 70's, as extreme example, many bikes had directionally ribbed front and lugged ,traction rear . I wouldn't want the ribbed one on the back!

 

[Guest]

Steve pretty much covered it all, but I will add a vote for the Shinko 230's if you are looking for lower priced but quality tires. I have a set on my 1100E and am totally satisfied with them. They are scrubbed edge to edge, offer solid traction wet or dry and work well on cool mornings (a necessity where I live). If we had vintage track days near me I would take the 1100E onto the track with the 230's without hesitation. The rear is getting flat spotted now, but not terribly (no funky handling yet) and it has around 5200km of mixed solo and two up riding on it. The ultimate recommendation - I will be replacing the rear next spring with another 230 without question.

I will also second Steve's recommendation to get a set of tire irons and a balancer and do your own tire changes. Our bias ply tires are easy to change by hand and you will pay for the tools the first time you do a set. On top of that, you will know it was done right and you will have gained a new skill. Youtube has instructional videos of how to change tires if you don't have the knowledge yet. You can look for dirt bike tire change videos as well, the procedure is exactly the same for both.

Not mentioned yet is that almost any new tire you buy will be labelled 'tubeless type'. That is no issue and you can run tubes inside tubeless tires with no problems if you want to go that way.


Mark

 

[Nessism]

Avon Roadriders make some models that can be used either front or rear. And Roadriders are some of the best tires available for a GS.

The 550 in question came from the factory with tubes inside the tires. If the front is running tubeless someone converted it. There are countless threads and much disagreement regarding the viability of both sides of the conversion to tubeless argument. Lets not start that again here...

Contrary to what Steve says I'd gladly run a set of tires more than 4 years if they look okay. I'd put the upper limit closer to 10 years.

 

[Brendan W]

Mine is tubed one end a tubeless the other in spite of both rims marked tubeless. Valves are different.
Front tyres work most braking and rears accelerating so it makes kind of sense to reverse direction if switching ends if you know what I mean.

 

[tom203]

Me too... I got my bike with 8 year old continentals, used them 4 more years. Switched to shinko 712s, got 7000 miles out of them - worked well, so I just put on another set.

 

[SunsetTwist]

First, thank you for all the replies and the helpful info. I can honestly say this forum is one of the best parts about working on a GS so thank you.

I was thinking about the shinko 230s after coming across some other forum posts earlier. Problem is I can't find any rear 230s in the 120/90/17 size. But it does exist in that size as a front tire. Do people usually just order two "front" tires in the appropriate sizes?

Also I was wondering about the tubeless question too. I couldn't find any kind of designation on the rims stating that they're tubeless so I'm was thinking to just order tubes to be safe when ordering the tires.

I'm actually in a motorcycle repair program at the local community college (City College of SF; sign up next semester if you're in the area! It's a really cheap DIY garage with some useful knowledge that needs more students) so I'll be using their tire station to do the work myself. I figure if there's a tube when i take it off, there'll be a new tube when I put it back on and I can't have put myself out too much.

Also someone mentioned the PO could have converted the wheels to tubeless? Is there something to check for this with the valve stem, sidewall, or...? I'm with you on not wanting to start another tubeless debate Nessism, i actually read THAT thread before posting in this one, just trying to figure out what I'm working with on this bike.

Again, many thanks and much appreciation. I actually just completed the motorcycle safety course for CA that allows you to waive the DMV driver's test TODAY. I'm really looking forward to getting a proper endorsement in a few weeks and having this bike ready to really ride.

 

[Guest]

Also I was wondering about the tubeless question too. I couldn't find any kind of designation on the rims stating that they're tubeless so I'm was thinking to just order tubes to be safe when ordering the tires.

It is possible both wheels are not tubeless rated. The other designation to look for is the 'MT' designation on the rim size. It should say something like MT2.50x17 or the like. The MT designates a rim that has the correct bead seat dimensions to run tubeless.

I agree with not restarting the tubeless debate. I think it boils down to your personal choice in terms of use and risk tolerance. Many people here run tubeless on wheels not so designated with no problems (including myself), but that is for each person to decide for themselves.

Also someone mentioned the PO could have converted the wheels to tubeless? Is there something to check for this with the valve stem, sidewall, or...?

You should be able to tell on the valve stems. Tubeless stems will be fitted tight to the rim and sealed with rubber washers of some sort while a tube valve stem will clearly stick through the rim with clearance in the hole and should only have a nut tightened onto the rim to hold it in place.


Mark

 

[SunsetTwist]

Ended up ordering a set of Shinko 230s from J&P. Got the front tire changed out this weekend but ran out of time for the rear for now.

Also I ended up getting two front tires since I couldn't find a 120/90/17 as a rear. Planning to reverse the indicated rotation to suit acceleration instead of stopping (thanks guys). I'll let you know how that one goes but that new front tire turned it into a real bike again. Before it felt like something threatening to shred a sidewall and take me down with it.

Took it out for my first cruise on it this past Sunday. Past two months of work finally came together to create something awesome.

Thanks again everyone!!