Buell Blast Tire Replacement Felix Wong

My Buell Blast—a.k.a., the replacement for Goldie the MGB—has proven to be a remarkably reliable, economical, serviceable and fun runabout. In stock form, however, there were two things I wanted to improve: 1) the handlebar height and reach, and 2) the tires. The former was accomplished by installing Bikemaster Superbike handlebars that resulted in a sportier, aggressive appearance more befitting of a sport bike. And this summer, I finally replaced the latter.

The stock Dunlop K330 tires had a fair amount of grip, but their useful life—especially the rear—was atrocious. I was only able to get about 3,800 miles off the rubber rolling at the back of the bike—and I am neither a portly nor heavy-handed rider with a habit of peeling out at every green light. The front tire was able to get about 7,500 miles before the tread bars started showing, which was acceptable, but still not stellar.

A search of the motorcycle forums revealed a couple of superior options for tread life, grip, and appearance: oversized Pirellis front and rear. The recommended tire for the front was the Pirelli Diablo Scooter 110/70-16, and for longest life in the rear, a Pirelli ST66 140/70-16. Both tires, according to Internet forum members, should last about 10,000 miles.

The front Pirelli is about half an inch wider than stock, and the rear one a full inch wider. In addition to looking cooler and meatier, their visibly rounder tread profile allows for easier motorcycle leaning and corner diving, and it’s not hard to imagine that they result in lower rolling resistance too.

No modifications were necessary to the motorcycle to accommodate either of these tires. (Reportedly, other oversized tires may not fit in the rear—even if they are labeled the same size as my new Pirelli ST66—without some hammering of a bracket which the rear shock is mounted to.)

Even though the front is a different model Pirelli tire than the rear, the Diablo Scooter and ST66 have similar tread patterns and hence seem like a good aesthetic match.

After a couple weeks of riding with both tires, it seems like my average fuel economy has remained the same: about 65 MPG in the summertime.

A final benefit is that in addition to having to be replaced less frequently than the stock Dunlops—saving both time and money right there—the Pirellis cost about $10-20 less than the stock tires! I purchased the Diablo Scooter and ST66 tires from AmericanMotoTire.com for $66 and $76, respectively, and shipping was free and no sales tax was collected. Motorcycle Superstore is another good source that I’ve ordered from in the past with good experiences.

Let me tell you that flogging the Buell along Centennial Rd. by the Horsetooth Reservoir was even more fun with these two new Italian shoes.

red Buell motorcycle by Horsetooth Reservoir

Tire Availability, September 2015

I have been getting reports that the Pirelli ST66 is no longer available, so I reached out to Pirelli USA asking for confirmation. They quickly replied with the following:

Thank you for writing in to us. The ST66 scooter tires were discontinued in the beginning of 2015, and replaced by the Diablo Scooter.

The OE tire for the Blast is the MT75, which was used as original equipment on the bike from 2005-2010 when HD cancelled the Buell bikes. We still make the MT75, and it is the suggested fitment for the bike.

The Pirelli MT75 is not oversized and wears about as quickly as the OEM Dunlops. So I would not recommend those.

I seem to recall that forum members tried using the Diablo Scooter tire (in oversized 140/70-16) on the rear, but were reporting tire life of only 6000 miles. Still, that is 50% longer than the OEM tires.

So if you cannot find any remaining stock of the Pirelli ST66, my current recommendation would be to get Diablo Scooter tires for both front and rear. Please email me if you have an alternate oversized tire recommendation instead.


Original Tires

  • Front: Dunlop K330 100/80-16 (4″ wide, 22″ outside diameter)
    7,500 miles before tread wear bars started showing
  • Rear: Dunlop K330 120/80-16 (4.5″ wide, ~23.5-24″? too hard to measure)
    3,800 miles before tread wear bars started showing

New Tires

  • Front: Pirelli Diablo Scooter 110/70-16 (4.5″ wide, 21.5″ outside diameter, 68″ outside circumference). [Latest prices on eBay]
    10,000 mile reported life-span according to forum members
  • Rear (#1 preference): Pirelli ST66 140/70-16 (5.5″ wide, ~23.5″? too hard to measure, 74″ circumference). [Latest prices on eBay] These were discontinued in January 2015.
    10,000 mile reported life-span according to forum members
  • Rear (#2 choice): Pirelli Diablo Scooter 140/70-16 (similar dimensions and tread pattern as the ST66). [Latest prices on eBay]
    6,000 mile reported life-span according to forum members

For all the above tires, you would want at least a P maximum speed rating (P=93 MPH, Q=99 MPH, R=106 MPH, etc.) because the Buell Blast’s top speed is 94-99 MPH according to forum members. If you are worried about that, get at least a Q speed rating. Personally I never exceed 80 MPH on my bike since that is already exceeding legal speed limits, so I would be fine with P.

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The Pirelli Diablo Scooter 110/70-16 front tire is about .5" wider than the stock Dunlop K330 100/80-16. (May 12, 2012)The Pirelli ST66 140/70-16 (left) is about 1" wider than the stock Dunlop K330 120/80-16. (May 12, 2012)Ready to head to the local motorcycle shop to have the new front tire installed for $50. (May 12, 2012)The Buell with the new Pirelli Diablo Scooter front tire installed. (May 19, 2012)I removed the rear wheel myself and brought it in with the new tire to be installed at a local motorcycle shop for $30. (July 12, 2012)The Pirelli ST66 installed on the rear. (July 14, 2012)

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30 comments on “Buell Blast Tire Replacement

  1. Comment by James Garrigan

    Hey , glad you post this I be been told countless times I can’t put a bigger tire on the rear !!!! So how are the tires holding up ? I’m looking to replace them Pirelli mt75 and hope that ur fat tire gets better wear . I got 3500 miles out of the last one . Do you think the stock exhaust flowing rt on the rear could be a problem too ?
    Thanks in advance for a response. Jamie

    • Comment by Felix

      Hi Jamie, thanks for your comment. Several hundred miles later, the tires are holding up beautifully. I wouldn’t worry about the gas from the stock exhaust flowing onto the rear tire—it shouldn’t affect durability.

      I’ll post an update when I need to replace the tires again. However,
      this could be a few years if the forum members who claimed that these tires can go 10,000 miles are correct!

  2. Comment by George

    How are the tires holding up?
    I have a 2003 Buell Blast with 3400 on the original tires and the back is just beyond the wear marks and need to replace it.

    Have you any experience with bar end weights?

    • Comment by Felix

      I have only 1100 and 700 miles on the new front and rear tires, respectively, but they are holding up well.

      They look great and handle well. So far there is no perceptible wear. I can see them lasting 10,000 miles as claimed by other riders.

      The rear tire, due to being a harder compound, is supposedly less “sticky” than the softer stock Dunlop, but I really can’t tell the difference. There has been no apparent difference in gas mileage, either.

      Since these tires cost less, look better, and should last much longer than the stock tires with no apparent performance detriment, I see no downside to them. Highly recommended.

      I have no experience with bar end weights.

  3. Comment by Dan

    Yes, my obvious first question is how are they wearing? This is for my girlfriends 2001 Blast. She is not aggressive but likes to try and keep up with me on an 1800 once in a while. Do you see any problems with the handling. Will she need to “relearn” the handling?

    Thanks for your post, btw.

    • Comment by Felix Wong

      I have put about 2500 miles on the new tires so far and they are holding up very well. No perceptible wear. Seem to handle as well in both wet and dry conditions, although admittedly I don’t really push the bike in corners especially when it rains.

  4. Comment by Aries

    Hey, just picked up a 2003 buell blast for 1,500 dollars for a second bike while my cafe project is being finished. I see your last post was April 8th this year, I just wanted to say thank you for posting the blog and the updates. I would like to know how much you weigh because I am a heavy rider and I need to buy new tires for this bike. I am 210lbs and tread life needs to be documented… being heavy makes it hard to count on any numbers but… I am thinking of ditching the bike end of summer so I doubt it will matter and might be a selling point to have cooler tires on there. Thanks again for your contributions to the motorcycle community. ~A

    • Comment by Felix

      Hi Aries, congratulations on your Buell Blast purchase.

      I weigh 145 lbs. Your weight + the bike’s weight is therefore about 10% more than my weight + my bike’s weight, but I’m not sure how much extra wear that would result in. I’m guessing not very much. Riding style (how hard you brake, accelerate and corner) probably has a much greater influence on tread wear.

      In any case I would highly recommend the tires.

      Have fun on your new bike!

  5. Comment by Aries


    Thanks, I purchased the Blast for a low price because it needed new tires, battery and regular maintenance. After reading your reviews on the tires I went ahead and picked up a matching set of Pirelli Diablo’s in 140/70, 110/70

    The only one available to me was the P rated tires, but with a buell doing mostly city riding I am sure I will get a few seasons out of the tires no problem (if I keep the bike, most likely going to sell it and continue my Cafe Racer project)

    On an unrelated note, I find many of the forums about Buell Blast going over very common issues that could be prevented such as cross threading spark plugs. Buells have some room to reach up to the spark plug without removing the tank, but it is only two bolts, two gas lines and two rubber bushings… takes 3 1/2 minutes. The Buell I just got broke down and the Junky sparkplug popped right out of the side. I did a very basic thread chaser and it was really alot of work to get the threads lined up. I put the new NGK iridium plug in to finish chasing the threads out… I could have done the top engine rebuild and put a Helicoil in it like everyone says to do… but… It riding season NOW… so if the repair does not last then it will be fixed if the threads break or fail. The spark plug was hard turning the last 8mm or so deep, but It was aligned correctly, and when I fired the Bike up.. It ran way better then before anything went wrong.. (I kinda side tracked into my own story here…) But anyways, just seeing this happen to me and reading about it online… Simply taking the time to thread the spark plug in with the tank off is the only way to do it… any other way is just a gamble with bad odds.

    Be safe and have fun rides!

      • Comment by kimberly

        awesome! thanks. my partner and i both just bought blasts a few months ago. it has been an adventure getting to know them/doing repairs. i am a first time motorcycle owner and its my first time doing a lot of simple things like changing oil/spark plug. pretty fun stuff! my rear tire is a Pirelli MT 75 and is as bald as an eagle. so i’m thinking i may try out the ST66. how is that holding up for you? BTW thanks for getting back to me so quickly!!

        • Comment by Dan

          I just put a Pirelli scooter tire on my gf’s 2001 Blast. What an improvement. Handling, wear and tear we’ll see but right off the bat it is visually a better tire than stock crap Dunlop. It look better on her bike too because it is slightly wider but don’t worry there is plenty of clearance.

          As far as a lift the bike is so light just buy any 2 piece online or even Harbor Freight (if you can find one). I only paid $100 for a front and rear lift and they work as they should. With the Pirelli you shouldn’t have to change it for around 10K miles vs stock Dunlop of 2500.

          If you like we can give you the info of where and how much for each the tire and lifts.

  6. Comment by frank

    Great writeup and pictures.

    I have a question or two about using scooter tires on a blast. Sorry if they are noob-ish in nature. This is my first blast. I have never owned a bike which had so many enthusiasts doing so many cool mods.

    I don’t have anyplace to change tires as I live in an apt.
    So I plan to buy online. Then take the 2 new tires and my blast into a repair shop for tire mounting and balancing. I was going to let the shop person remove the old tires from the bike, mount & balance the new tires and then put them back on the blast.

    1. When taking “over-sized” scooter tires into a cycle shop for mounting, have you run into any issues where the shop declined to install them because they were “over-sized”?
    2. And/or they were “scooter tires” and you were trying to put them on a motorcycle?
    I just wondered if any shop have said anything like:
    “Hey. Your bike has 100/80-16 front tires and 120/80-16 rear tires. These tires you brought in with you are “too large” for this bike. We won’t mount them for you, as it could cause us a liability issue if “anything happens” to you while riding with over-sized tires”
    (I ask because I didn’t want to buy 2 new over-sized scooter tires, if a lot shops were hesitant to install them for you).

    3. Would there be any “more-miles-per-tire” longevity benefit to using scooter tires of the same “OEM size” that the blast comes with? (100/80-16 front and 120/80-16 rear) ?
    3. Or is the ability to get “more-miles-per-tire” based primarily on the fact that the
    tires ARE over-sized; rather than the scooter tire’s composition materials?

    • Comment by Felix

      Hi Frank. Thanks for stopping by my site and for your comments.

      Regarding your questions:
      1. I’ve had no issues with the cycle shop declining or even questioning whether to install the oversized tire on the wheel I brought in. Granted, I’ve only done this once.
      2. No questions about it being a “scooter tire” either.
      3. I think the longevity is primarily due to the tire compound. But if there was going to be a difference in longevity between two different-sized tires—all other factors being equal—I would expect the oversized tire to last slightly longer.
      4. It’s the durometer of the tire that is most important for longevity, I think.

    • Comment by Dan

      I had no problem with my gf’s scooter tires being mounted by a dealer. And let’s face it they are not that much bigger. It’s a more rounded tire. Tread wear is all tire material and tire pressure. My gf noticed much better handling too. Just call each shop first with your intentions. They will tell you yah or nah.

  7. Comment by Armando

    Hi guys.
    I bought a 2002 Blast a couple of weeks ago and just got a matching set of ST66s to be mounted on this weekend. My question here is, what pressure should they be inflated to?

    • Comment by Felix Wong

      This is a good question. I inflate mine to the same pressure as stock (28 psi front; 30 psi rear), but now that I think of it, since the tires are larger, you should be able to use lower pressure for the same firmness. How much lower is open to speculation.

  8. Comment by Rafael

    Felix, Thank you so much for your detailed post both on the tire replacement as well as the handlebars. Replacing the tires on my Buell will definitely give the rear a meaner and beefier look to it especially with the handlebars and the new exhaust. Now with the tire being wider did you run into any issues with the speedometer? Is it still reading accurately? And lastly, Do you have any thoughts on getting a tachometer compatible with the Blast?

    • Comment by Felix Wong

      Thanks for stopping by my website and for your comment.

      The speedometer seems reasonably accurate with the tires; if anything, maybe 5% too high. I’ve gone down a street with a radar sign while the speedometer read 30 mph, and the radar sign fluctuated between 28 and 29 mph.

      I’m not sure how accurate the speedometer was before the tire swap, but any change, if any, wasn’t apparent to me.

      I fleetingly thought about getting a tach for the Blast, but never acted on it. I think I like the simplicity of a single gauge.

      If you ever get one and install it, please let me know how it goes.

  9. Comment by Caleb

    Thanks for the info. One obvious question that I don’t see the answer to. Did the oversize tires make your speedometer incorrect?

    • Comment by Felix Wong

      I can’t say for certain the speedo is incorrect or whether the new tires even caused a change. Many speedometers on cars are off by 1-3 MPH so it wouldn’t surprise me if the speedometer on the Buell is off by a little bit (with or without the tire change).

      I am certain that the speedo is at least ballpark and reasonably accurate. Also, if anything, it reads (very slightly) high on my Buell based off of one experience riding on a street with a radar speed sign. I’d rather have it this way; reduced chance of a speeding ticket.

  10. Comment by yu jin

    hi felix, does the wider and taller rear tire rub on anything when you first put it on the bike? thanks

  11. Comment by Mike

    Felix, sorry for the questions but what speed rating should the tires be? P/94mph, S/112mph and also is the ST66 tire found in the scooter category like the Diablo front tire? Thanks Mike

    • Comment by Felix Wong

      The top speed of a Buell Blast is said to be 94-99 MPH, so a P-rating should be “good enough.” Personally I never exceed 80 MPH, so I would be fine with that. I would get the S if the price difference was small, however.

      The ST66 may be listed in either motorcycle or scooter categories; I’ve seen them in both in the past.

      I just did a quick search and was able to find the Pirelli Diablo Scooter 110/70-16 front tire on eBay.

      The Pirelli ST66 was discontinued in January 2015. But a Bing search yielded the following source that may have some remaining ones in stock: http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=4644

      Otherwise, purchase a Pirelli Diablo Scooter 140/70-16 rear tire instead. Tire life on that is said to be only 6000 miles, but that is still much better than the original. Good luck!

  12. Comment by Fred Tucker

    Hey man. I really like your blog about the maintenance and upgrading of your Buell Blast. I’m going to change my handlebars to the same ones you blogged about soon. I was trying to find the tires you used in this swap to change over to them as well, but it seems as though the ST66 isn’t sold in that size any longer. Do you happen to know what other tire might be a good replacement for it that will get similar mileage? Thanks in advance.

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