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Thunderbolt Conversion?

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T O P I C R E V I E W
dlbott	Posted - 03/25/2012 : 09:15:26 Hey, has anyone ever tried to convert a thunderbolt to a high racer. I would think the larger tire on the front with smaller area touching the surface of the road would increase speed dramatically. i wonder what would be involved and how it would be done. I am not very handy, lol, would need help and would like to know how it would be possible if it is.... thanks don Visit www.sleepaidreviews.com for help with insomnia.
13 L A T E S T R E P L I E S (Newest First)
dlbott	Posted - 04/01/2012 : 18:04:14 Larry, yes, thank you so much for eloquently explaining exactly what I was trying to put into words, lol. Great job... you are definitely smarter than I am, lol, or at least well versed. Thank you, exactly what I meant and would love to do with my thunderbolt. I think it would be awesome and so fast. Oh, i found where I think the bike I was riding was made, at least it looked like one of their high racers. But boy nice bikes but expensive, lol.. check em out: http://www.performer.com.tw/2010/user/product_2.php?wp=05&sno=00465 no affiliation just thought u guys might want to see what I think it was, look at their high racers, it was like them, it was fast, lol. thanks again larry don Visit www.sleepaidreviews.com for help with insomnia.
Larry Lem	Posted - 03/31/2012 : 21:34:16 Don, I think there was just some minor confusion over some of the descriptions and then one mistake made on tire pressure and contact patch. "the larger smaller diameter road wheel was way faster." probably means large diameter wheel (700C, 650C, 26") vs small diameter (451, 406, 341, 305) and smaller diameter means "narrower" tires Usually the 700C tires can be inflated to greater pressures and without going overboard, higher pressures usually result in lower rolling resistance (though Lennard Zinn is arguing the opposite on Velonews now with no supporting evidence). There are some narrow, high pressure, small diameter tires, but not nearly the selection as with 700C. For the same tire pressure whether on a 700C and 406 tire, if the load is the same, the area of the contact patch will be the same. I think most of us have found that on real-world road surfaces that the larger diameter wheels do roll "faster" than small diameter wheels. No argument against that. Again, everyone here endorses your thoughts to experiment with the larger diameter, narrower tire change and hope it works out well. Good Luck! Larry Lem
Speedbiker	Posted - 03/31/2012 : 18:51:48 Don, while your physics are questionable, I think the moditication might work out very well. Improved weight bias, better tire dynamics, more aero body position. I hope it works for you. Thom Ollinger Nirvana Bicycles Coslinger Speedbike Team
dlbott	Posted - 03/31/2012 : 15:44:21 Speedy, I don't claim to be a smarty farty. I stated it very clearly. If you have ever ridden a high racer you see fantastic speed difference. There is no comparison to the smaller, wider front wheel. It is much, much faster. It is mildly hilly here and you could also see a difference in climbing. The climbing was only because I could push harder on the larger wheel, at least that is what it felt like the reason was. Control does take a little getting used to but if the seat is adjusted correctly you can get used to it quickly. I don't claim to be smart like you, the proof is in the pudding so to speak. Your experience maybe different than what mine was. For me there is no comparison, the larger smaller diameter road wheel was way faster. i don't remember what the brand on the bike was but everything else was similar, weight, above steering, 21 speeds, gear ratio's appeared to be the same. The 26 front wheel bike did have a front steering that was adjustable where my thunderbolt's is not, it is fixed. That too seemed to help get that extra torque. I am sorry I seemed to strike a chord with you speedy. You may not have the same experience. My observations are based not on physics but actual riding. Try it and maybe you will too. If not it is ok that you disagree. Great thing is it is ok for you to have a different opinion. Wife is a Republican but I still love her, lol... Great thread... I will keep everyone posted on the progress, still looking for a front fork that will fit and work, the seat too may need some adjustment somehow. Thanks all Visit www.sleepaidreviews.com for help with insomnia.
calfeenated	Posted - 03/30/2012 : 19:52:09 For anyone who is interested, pictures of the Extra Large Thunderbolt frame are in the bike part swap section of this forum... And here too... https://picasaweb.google.com/100530817957151973948/ThunderboltFrame?authuser=0&authkey=Gv1sRgCNT0tojAodWY6AE&feat=directlink Mark.
Speedbiker	Posted - 03/30/2012 : 10:20:28 Don, please don't take a job teaching physics. Enjoy your bike.
dlbott	Posted - 03/30/2012 : 09:41:34 My point was that the larger 26 inch wheel and high performance tire has very little surface touching the ground. This translates into much more speed. The smaller wider tires have much more surface on the road. This does not translate to speed, it translates to friction. You also get much more torque on the larger wheel. Hey, try this for yourself, If you have a chance to try a high racer as opposed to one with the smaller front tire you will see a tremendous speed difference. You can get the same speed increase from changing the 26 inch upright tires from mountain bike tires to road tires. Of course you need the mountain bike tires if you are riding off road. If you are riding on the road and want speed you will want the smaller diameter road tire. Look forward to hearing from you Mark, would love to get the parts to try this conversion. thanks all don Visit www.sleepaidreviews.com for help with insomnia.
Speedbiker	Posted - 03/29/2012 : 21:14:00 Bigger wheel=smaller tire patch? Hmm, that's new. Still might work quite well.
dlbott	Posted - 03/29/2012 : 17:40:56 Hey Mark, It is the 26 x 20, wow that would be awesome if you had some parts I could use to try this conversion. I think it would be incredibly of you to share with me. I think it would be awesome as a high racer, it climbs really well and I always thought as a high racer I could blow my up right riding friends away. The 26 wheel has so much less wheel on the surface. My email is dlbott@hotmail.com if you really want to share some parts for this conversion. I am really not sure what it will take to do it. I am out in the country in southern louisiana. Thanks Don Visit www.sleepaidreviews.com for help with insomnia.
calfeenated	Posted - 03/28/2012 : 20:28:01 What size thunderbolt do you have? Is it the 26-16 combination or the larger 26-20 combo? I have an extra large Thunderbolt frame that is not doing anything right now. I'm 5ft 11 with shorter legs and a longer torso and I would run the boom as short as I could with the seat as far forward as possible and it still felt just a tad too long. Right up until I decided to go a different route I thought about replacing the front fork with a 24" because I have a nice stockpile of 24" wheels and tires but I never got around to it. 24" wheels really are only 22.5 in actual diameter so they wouldn't change the head angle too much, it would give you a bit more trail so high speed stability might be improved. Mark.
dlbott	Posted - 03/27/2012 : 10:08:17 Wow, that bachetta frame is awesome but way, way, out of any price range I will be able to have in my lifetime, lol. Poor guy on disability raising his granddaughter. Unfortunately, I am not very handy. I guess maybe I will have to try and find a mechanic who can help me. Right now bike is not functioning, needs some tlc. I really need to learn how to make adjustments etc. Need a new tire. Don't have a garage and the winter in the barn shed was not kind to her, lol. I do have a second bike that also needs some tlc, i think it was called an R40. Not sure. It has underhand steering which is really better for me as I have nerve damage and it is hard to raise arms. I am not sure if it could be raised to a 26 inch front wheel or not. I thank everyone for suggestions. don Visit www.sleepaidreviews.com for help with insomnia.
Jeff Wills	Posted - 03/26/2012 : 08:10:46 I think it's possible, but you'll have to be a decent bike mechanic to handle it. I would worry about the change in geometry- leaning the bike that much could cause the handling to be funky (or it might not) and you'll definitely need to contend with more heel strike. I would suggest using your existing parts and putting them on a Bacchetta highracer frame kit: http://www.bacchettabikes.com/bikes/frame-kits.php __________________ Jeff Wills All my bikes: http://home.comcast.net/~jeff_wills/Gallery/index.html
Larry Lem	Posted - 03/25/2012 : 11:46:28 It seems like an easy experiment to try. Just a new fork and front wheel, all "bolt-on" parts. Could be fun and fast, could be a nightmare. Just do it and report back. Larry Lem

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