Whatever happend to Big Rear tires?

[Olmy]

I have been looking for 140/90 X 18 rear tire with aggressive intermediate knobbies. I have a metzler on the back of my 83' ktm 495 with that size and it is worn down.  I would like to get a couple wide tires like that but can't find them.  Biggest I found was a 130/90.  These tires will go on 83'KTM 495 and 02'XR 650 R.  Any information and suggestions would be a great help.
Thanks

[Dwight Rudder]

No one runs tires that big. Very few bikes , even open class machines have enough power to pull them. The Pirelli MT16 rear in the 450X18 ( 120/100X18 ) is a huge tire and I wouldn't recommend it for anything less than what you have. I run it on my PENTON(KTM)525EXC and I ran it on my XR600s.  I ran it on my XR440 but I would say it was almost too big.
Very few of the vintage bikes actually have enough clearance for these oversized tires. For your infomation a 130/90X18 is same size as a 450X18 and a 5.10X18.
If you insist Cheng Shin has a 5.60X18 in the C760 series and
a 5.30X18 in the C755
Duro makes a 5.40X18 in the HF335 series .
All these tires are available through your Parts Unlimited Dealer

Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.

[Olmy]

Thanks a lot for the information.  All points noted however I will steer clear of the cheng schin and duro tires.  I will go with the 120/100X18.
Thanks again.

[t20sl]

IRC makes a 140-80-18 Knobby , model number M5B.  It is a great soft terain tire.  Very tall knobs and has always worn well on the back of my 250cc enduro bikes.  Here in Ohio our enduro's have lots of clay and the wider the better.  I don't agree with most bikes not having enough power to pull that big of tire.  Usually in muddy conditions the tires are spinning on top of the mud anyway.  Have won several enduros on my IT175, IT200 with 550-18 Dunlop K88 knobbies back in the day.  Everyone said that was too much tire also, but it worked!
Michelin also has a 140/80-18.  Find a dealer that has Parts Unlimited as a distributor.

[tlanders]

Dwight,

You convinced me about the Pirelli's and I have put the MT16 400x18 on my Piner and the 450x18 on the hare scrambler, the mint 400 and my 250 MC5. They have done a good job. However, I notice that an awful lot of the MXers are wearing the Michelin S12 and M12 tires including Kevin Brown. I bought a junker '79 KTM and it had a new M12 on the rear. Putting it next to the MT16 it was obvious that the M12 was considerably smaller in outside diameter. This appeals to me since I am 5'9" and on the taller '78 and '79 bikes, I like that fact that it lowers the bike. What say thou???

Teddy

[Olmy]

I hate to bring up an old question... For my 83'KTM 495 thinking of puting a Interco tera-flex 140x80x18.  I hear it is a pretty good tire. Since this is the ultimate site for motorcross information I want your opinion of this tire.  I ride both Ohio clay/mud and WVa. hard pack.  Thanks...
Mike

[tomale]

Hey Olmy,
Back in the day I use to run metzlers on my Maico. they were 450/18's
I had a dunlop on my bike but they did not wear that well on the hard pack trackes of Northern Calif. Last year when I went back to racing The michelin tires were recommended to me and I really like them. I had put a S12 130/18 on my 76 mc5 250 and it was too big not that it would not spin but it was just too big for the rim. It interfered with the operation of the chain. I replaced it with a S12 120/18 and have really enjoyed it. I have 7 races on it 4 motos each plus practices and a number of trail rides and the tire is just now begining to look like it is wearing.  Most of the track time is on a sandy/loam surface but I have rode some really knarly trails that looked more like river beds than trails and they have held up really well. I payed more money but they have really lasted a lot longer than I thought. What ever you do, go with a good tire... leave the cheap stuff to people who only ride on sunny afternoons.[8D]
By the way, the front tire is important too, if you have not replaced the front tire and it has been on there for a very long time, it is time to replace it. Old tires get brittle and do not work all that well, regardless of how they look. Try a new tire... you will like it.  Ask me how I know....

Thom Green,I own and ride a 76 250 MC5 MX which I bought new.

[tlanders]

I finished building the 1980 MC80 with reed valved 400 engine in it and took it to Florida and won my first moto on it. It's great, but the worn Michelin M12 120/90 was spinning too much. Sprockets were 13/52. So I went to 14/52 and went to the MOVMX races with it last weekend - what a difference, however I feel there is more traction to be had. So I just put a new Michelin 130/80-18 S12 on the rear and a Michelin 80/100-21 M12 on the front. Mike Lenz said this was the "hot" combo. Can't wait 'til Texas this weekend to find out the results!!! In Dwight's favorite tire, the Pirelli MT16, the 4.50-18 is much bigger than the 130/80-18 Michelin. I wanted the 80 lower profile tire to lower the bike.

Teddy

[tomale]

I sure have enjoyed my michelins, Thanks for including the gear rations  I was just looking at the the sprockest on the 400 and noticed that although the rear was a 52 the front was a 15. I thought that was too tall unless it had been set up for high desert.
I have heard of guys setting up big thumpers with tall gears so that it would not wheelie so much and it would broaden the the gears changes. Ie. If you only get say... 25 yards before you have to shift between 2nd and 3rd then going to a taller gear would widen that to say 35 yards, thus shifting less and the bike does not spin so much. This might be an advantage if you have alot of corners that fall with in that range and it does not cause you bike to stall in the corners... etc.
I was thinking that a 15 countershaft sprocket was too large and I needed to step down to a 14 besides I just bought a guard to fit on the bike and it will not fit with that 15 but it is nice to know that I am in the ball park. [:0]

Thom Green,I own and ride a 76 250 MC5 MX which I bought new.

[Mike Lenz]

OLMY, I have a HUGE Michlin 140/80-18 that is too big for my mc-5 I will sell CHEAP, Ist a S12 Model.

[Olmy]

Thanks Mike for the offer, but I picked two tires up yesterday.  I bought the 140/80/18 Tera-Flex from Interco.  I found a guy that had them in his garage New!  He had one mounted on his KTM 520 and he said they work great on everything.  I must say I am impressed because they are HUGE!!  Knobs are almost one full inch high!!  I put this tire next to an old dunlop 140/80/18 and the Tera-Flex makes the dunlop look like it should be on an 80cc bike... Not a KTM 495.  Well to be quite honest this tire may be to big.  I am gonna mount them on the 83' 495 MXC and my XR650R.  I will let ya know the results in the next month or so of riding and trialing this tire.
Thanks

[Olmy]

Well yesterday was the first ride with the Interco Tera-Flex 140/80/18.  It barely fits on my XR 650R.  It performed great in the muck.  Problem is I get muck all over on the rare occasion that the tire spins.  Throws serious amounts of huge mud clumps.  It hooked up extremely well on soft and intermediate terrain.  Still have to try it out on hard pack.  I can't wait to put this tire on my KTM 495 MXC.
Mike

[Dwight Rudder]

quote:Originally posted by tlanders

I finished building the 1980 MC80 with reed valved 400 engine in it and took it to Florida and won my first moto on it. It's great, but the worn Michelin M12 120/90 was spinning too much. Sprockets were 13/52. So I went to 14/52 and went to the MOVMX races with it last weekend - what a difference, however I feel there is more traction to be had. So I just put a new Michelin 130/80-18 S12 on the rear and a Michelin 80/100-21 M12 on the front. Mike Lenz said this was the "hot" combo. Can't wait 'til Texas this weekend to find out the results!!! In Dwight's favorite tire, the Pirelli MT16, the 4.50-18 is much bigger than the 130/80-18 Michelin. I wanted the 80 lower profile tire to lower the bike.
Teddy

Teddy, you will find that the 130/80X18 Michelin is the same size as your 400X18 ( 110/100X18 ) MT16 Pirelli. I dislike strongly the M12 and the S12 is a good tire on a modern bike but I don't find I can slide very well with it. It tends to hook up too good. I love the MT16s on my vintage bikes and also use them on my modern bikes. They work well and have a vintage look to them. Use vintage type products on vintage bikes. Otherwise why not go back to racing modern bikes ?
I though the whole idea is to recreate an era. Not to ride modern stuff.
IMHO,
Dwight

Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.

[Dwight Rudder]

PS:
 I think you will find that the 400X18 -  110/100X18 MT16 is same size as the old Metezler Motocross/Enduro 450X18. The Smaller MT16 will work on most Vintage bikes of 175cc and up. But it better be a strong 175cc, like the KTM powered Jackpiner or a Can-Am. Most Post Vintage 175s can pull with no problems.
Cher'o,
Dwight

Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.