J-Madd Posted June 24, 2013 Report Share Posted June 24, 2013 We used other methods this weekend. Didn't touch the clutch. Some buddys that messed with the clutch lost ET. So we didn't follow 1 Quote Link to comment Share on other sites More sharing options...
sandbum80 Posted June 24, 2013 Report Share Posted June 24, 2013 The reason I asked about stock (new) spring pressure was not because I wanted to use as a base but see the diffrence in pressure from used to new. I have all my baseline recorded, I ended up having to subdtanially lower spring pressure on thursday to get out of hole, ended up a few gear changes and finally starting in 1st ended up picking up around 11mph by end of weekend Quote Link to comment Share on other sites More sharing options...
Sweet1 Posted June 25, 2013 Report Share Posted June 25, 2013 How does all this work for outlaw style racing,hillshooting where you can hotlap? coming from car racing i love seeing all the info going to bikes. Quote Link to comment Share on other sites More sharing options...
phunt Posted June 25, 2013 Report Share Posted June 25, 2013 used the infromation from this thread and some awesome advise from chris from wheelman chassis this weekend and went from running 4.40s off the trailer pulling 1.6 60s to running 4.0s with 1.4 60s just from a gear change and some clutch tweaking... i am a believer for sure now and cant wait to get a chance to play with it more. I know there is a ton left in it thanks for sharing the info you have in this thread good job, there is some good info here that's for sure. The rain has keep me from testing for the past two week(dang rain) I'm so ready to do more testing. Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted June 26, 2013 Author Report Share Posted June 26, 2013 The reason I asked about stock (new) spring pressure was not because I wanted to use as a base but see the diffrence in pressure from used to new. I have all my baseline recorded, I ended up having to subdtanially lower spring pressure on thursday to get out of hole, ended up a few gear changes and finally starting in 1st ended up picking up around 11mph by end of weekend Your base between new & used springs should be compared using your installed height. Someone might be able to help you out if you provide the height. How does all this work for outlaw style racing,hillshooting where you can hotlap? coming from car racing i love seeing all the info going to bikes. We hot lap our bike & used it hill shooting. We were able to get about 4 hot laps with lots of slip in our clutch. That was done on a race gas bike with cooling mods in the clutch pack. Alky will help with the heat issue, plus most people don't run close to the clutch slip we do. The only way to find out is to make 3 or 4 hot laps with your set-up. Then do a quick inspection of your clutch pack after the test & check the heat in the steels. good job, there is some good info here that's for sure. The rain has keep me from testing for the past two week(dang rain) I'm so ready to do more testing. I'm predicting high 1.20 60's for phunt in the near future! Quote Link to comment Share on other sites More sharing options...
J-Madd Posted June 26, 2013 Report Share Posted June 26, 2013 High 1.2s on sand/dirt? Quote Link to comment Share on other sites More sharing options...
phunt Posted June 26, 2013 Report Share Posted June 26, 2013 I have always ran my bike with me on it (210lbs) and could never compete with jocks, after crying( as they say) about weight limits I decided to go as light as possible with my cub. I always knew my bike had just as hp as other bike just couldn't show it. Now that I am getting this clutch thing down that makes it better. My plan is to go to Kentucky at the last race for the record. If I don't set record just as long as I'm faster than the next bike. Currie motor sports runs the same track I race, fastest his bike went 3.76 1.37 60ft fastest my bike went 3.69 1.304 60ft. my 60 ft results are from this topic... That's what's going to hurt these classes no weight limits,its not about spending 4 grand in a motor any more its about spending 8 grand on a frame setup. I'm not a builder, just the average Joe that's loves drag racing. Quote Link to comment Share on other sites More sharing options...
J-Madd Posted June 26, 2013 Report Share Posted June 26, 2013 I have always ran my bike with me on it (210lbs) and could never compete with jocks, after crying( as they say) about weight limits I decided to go as light as possible with my cub. I always knew my bike had just as hp as other bike just couldn't show it. Now that I am getting this clutch thing down that makes it better. My plan is to go to Kentucky at the last race for the record. If I don't set record just as long as I'm faster than the next bike. Currie motor sports runs the same track I race, fastest his bike went 3.76 1.37 60ft fastest my bike went 3.69 1.304 60ft. my 60 ft results are from this topic... Very impressive. Good job and good luck at Sheltons. 1 Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted June 27, 2013 Author Report Share Posted June 27, 2013 STY, have you ever set any records in the 300', 1/8 etc etc? Seeing we are 300' rookies, we have no lightweight jockeys & no light weight frames. The answer would be no. Are we competitive heads up, index & bracket racing, yes. That's really all that matters to us is winning races. Our primary distance we run on asphalt is 1/4. The set-up for 1/8 mile is different, but we do well there also. Have I set any records on asphalt, no. The only people I know that claim records is Puerto Rico. There's no sanctioning organization that keeps records that I know of. I can count on one hand the people that can match or better our 1/4 mile ET. As for builder's, I only know one that's has stepped up to the plate to run that distance. They either say it can not be done. Like one of my previous builder's or they choose not to try for whatever reasons. Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted July 23, 2013 Author Report Share Posted July 23, 2013 I have gotten a few questions on measuring spring height. I can't remember if I posted the piece of tubing I cut to help with the measurement. Anyway, I'm going to post it up. We cut a piece of tubing on the lathe to a set height of 1.8". The tubing dia. is 5/8 or 6.25, the inside dia. is .450. This is how it looks installed & ready to take the installed height measurement. This is taking the depth measurement from the top of the tubing/sleeve down to the inner hub standoff. You then take that measurement & subtract it from your known tubing/sleeve height to get your spring installed height. This can be done without the tubing/sleeve, but this makes it much easier to get a more accurate measurement. I know in my 1st photos showing measuring spring installed height. I showed measuring the step on the lock-up side of the spring. Most lock-ups that I know of don't come with that step. So there's nothing to measure on the lock-up. We have a Direct drive that's like that, but we are going to cut a step into the spring pads like our multi-stage. Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted July 23, 2013 Author Report Share Posted July 23, 2013 This was asked in a PM & I asked if I could answer it in open forum. That's the way I prefer to answer most questions anyway. "How do you know your gearing is correct and its time to start fine tuning the clutch. 300ft sand if it matters." I'll start with the gearing & this is just my opinion. Most will know the rpm where they make peak HP if they've been on the dyno. The idea is to have the motor at the peak HP rpm somewhere around the finish line. That's in the gear you want to finish in, for 300' that would be 5th gear for most & 4th gear for some. We choose to do it a little differently with hitting the peak HP rpm well before the finish line. While we tend to lose a little mph we make up for it with a quicker ET. I'll use a 1/4 mile run as an example: our old motor made peak HP @ 9,7000 rpm. We shifted it mostly between 10,000-10,200 rpm & shifted into 6th gear before the 1/8 mile. On our best runs we would be around 10,700 rpm at the finish line. Well, over our peak HP rpm. We use this method for 300', hill shooting, 1/8 mile & 1/4 mile. The gear we finish the run is different each, except 300' & hill shooting. The clutch tuning is primarily used for the 1st 20' to 40' of the run approximately. The 60' times tells if you going the right or wrong way with clutch tuning. So, to sum it up. IMO, gearing for the most part is getting your RPM right at the set distance you are running. Clutch tuning is getting your lowest 60' time possible. NOTE: Gearing does play a factor in the 60', but we primarily use it to get our desired rpm & mph at the finish line. Clutch tuning is used to get the quickest 60' times as possible.The clutch when not right (arm weight) will affect things past the 60'. This usually shows up on the 3-4 shift & the 4-5 shift if you are leaving in 2nd gear for 300'. This will affect your mph also because of clutch slippage. Quote Link to comment Share on other sites More sharing options...
dozer Posted July 24, 2013 Report Share Posted July 24, 2013 Now that you gave us a ball park idea on gearing, what about paddle count. It seems like some faster 300 ft bikes run a lot of paddle and win the race in the first 60ft vs tryin to power around someone. what ive seen with fast smaller motors is "too much paddle" lots of rpm and lower gearing . Just wanted to hear your thoughts. Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted July 24, 2013 Author Report Share Posted July 24, 2013 Now that you gave us a ball park idea on gearing, what about paddle count. It seems like some faster 300 ft bikes run a lot of paddle and win the race in the first 60ft vs tryin to power around someone. what ive seen with fast smaller motors is "too much paddle" lots of rpm and lower gearing . Just wanted to hear your thoughts. I consider myself a rookie at 300', but we've had some pretty good success doing it. I wish some other people would speak up with their opinions on the 300'. 1st & foremost ET wins races, plain & simple. Most of your ET comes early in the run, that's why we focus on the 60' time. Don't get me wrong we pay attention to the mph, but to us it's secondary between the two. At 1st we were under paddled running a 22x11x8 12 paddle extreme. While we ran good numbers that way. We had problems down track, spinning in 3rd & 4th gear. Plus, it was hard to shift into those gears also. My fix for them problems was a 22x11x8 14 paddle ripper. That's when we were told my many we had too much paddle. The guy didn't even want to sell me the tires, because he thought they were too much for our bike. Anyway, we ended up losing a little 60' time, but was still in the high 1.30 range. We didn't have any more problems with wheel spin or shifting. We picked up a good amount of ET in the mid track & added an easy 3 mph to our trap speeds. We also ran a 82" RO 16 paddle stg. ripper on it. The bike pulled them, but we didn't spend enough time with the set-up. All of this was run with our 443 cub in my signature photo. I considered it a small motor & it had lots of tire. We launched it at 10,000 rpm, shifted around 10,200 & went thru the 300' timers at 10,000+ rpm. We launched in 1st gear with a 2.54 ratio & ran anywhere from a 17front/39-43 rear sprockets. Quote Link to comment Share on other sites More sharing options...
dozer Posted July 28, 2013 Report Share Posted July 28, 2013 once you get a limiter on the bike, How to you determine what rpm to launch at? should you launch at peak hp/tq ? Quote Link to comment Share on other sites More sharing options...
SlowerThanYou Posted July 28, 2013 Author Report Share Posted July 28, 2013 once you get a limiter on the bike, How to you determine what rpm to launch at? should you launch at hp/tq ? At peak hp/tq I have no definitive answer for the questions. I can give you some ideas & guidelines we have used. On our cub motor using it on asphalt, hill shooting & 300'. The easy answers are we used a minimum of 7,000 rpm - 10,200 rpm. The nice thing about changing the launch rpm is, it can be used for different aspects of racing. Like reaction times & changing how the clutch reacts to name a couple. Reaction times can be changed within reason by changing the launch rpm. Usually we raise the launch rpm to quicken the reaction times & the opposite to slow them down. We also tend have a higher rpm for .400 pro light & the opposite for a .500 full/sportsman tree. We also use launch rpm changes to change how the clutch reacts. This is much simpler than going into & changing the clutch setting. Usually taking rpm away, loads the clutch more allowing more slip initially. Plus, it slows down the clutch lock-up. Now adding rpm, it gets a little harder to explain. Usually what happens is it hits both the clutch & tires harder. That causes the clutch to initially slip, but the tires tend to spin. This causes the clutch lock-up to be very aggressive & locks the clutch up very quickly. Now, for the question of launching at peak hp or tq. IMO, you can set the clutch up with other things to make either work well. With our cub motor we were closer to peak hp rather than tq. With the DMX we are using the opposite to start with, but don't have enough data on that combo yet. Quote Link to comment Share on other sites More sharing options...
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