March 13th, 2016, 07:22 AM | #41 | |
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When you get over 400F, the time you can spend there without altering the heat treating gets pretty short. At 375F to 380F you get about an hour before you start to get close. Most of the time the wheel spends about 15 minutes at that temp. The problems start when people "outgas" the wheels at 450F to release trapped gasses or "burn-off" the existing coating at 800F. It happens. For bearing installation, I would think 200F would be plenty. At that temp it would take hours and hours to even get close to altering the heat treating. |
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March 13th, 2016, 07:45 AM | #42 |
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Just warm is probably good enough. I could still touch the wheels with my fingers and not feel like it was burning. Just a heat gun will warm them enough. Definitely don't heat the wheel enough that is burns you. If bearings are cold the rim is warm. Then the bearings should just push in with you fingers.
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March 13th, 2016, 10:22 AM | #43 | |
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Eric is dealing with terminal velocities, not acceleration. So all else the same, a difference in rider weight doesn't really factor into the equation. Obviously there's limitations to that statement because the bike does have to accelerate within a reasonable distance before the timing zone, but still. The only factors in terminal velocity calculations are tractive force (power transferred to the road) and resistance to movement (bearing friction, rolling resistance, aero drag etc etc). Rolling resistance IS a function of weight, so technically weight does come into play, but rolling resistance and bearing friction are so small in comparison to the aero drag, that for the sake of our discussion, weight can be dismissed as a concern. |
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March 13th, 2016, 10:37 AM | #44 |
in your machine
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Ahhh okay gotcha
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March 13th, 2016, 11:20 AM | #45 | |
Rev Limiter
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Sport Rider did an article on aerodynamics and Land Speed Racing a few years ago, and compared a smaller rider and a bigger rider - the bigger rider was more aerodynamic. That's because he filled the low pressure void better than the smaller rider. It was also on a big bike (Busa I think), so it's not going to be the same on something like a Ninja 250, small bike, or one without fairings. Just something to consider. The right answer isn't always the obvious one. |
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March 13th, 2016, 11:33 AM | #46 |
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The real difference is the tuck. If your back is flat then there is less void behind you.
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March 13th, 2016, 11:52 AM | #47 | |
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Spend your evenings researching on scholar.google.com looking for research papers about CFD and/or wind tunnel tests on motorcycles. Check for sources like SAE or ASME or maybe even AIAA journals. Look into other topics like trip wires or spoilers when you do your searching. Trip wires are a way to induce small turbulence in order to contain the flow better so it doesn't separate into large turbulent regions. The idea is it will follow the surface of your body longer. Skin friction << form friction, therefore taking a small hit on skin friction ddramatically reduces form friction. most studies will have fancy pictures like this, not useful for much without knowing their scale/variables/whatever. But they look neat!!! |
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March 13th, 2016, 01:46 PM | #48 |
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I have spent many many eavnings researching aerodynamics. What I learned is to take all the fairings off and run the motorcycle in a class that does not use them. The money spent to build paint and mount the fairings on a motorcycle that is only going 125 mph is better spent on engine development. I say that as a joke . But all jokes have there basis in reality.
Each speed has its own aerodynamic sweet spot. So somthing that goes 200 might not work at 100 and it might not work at 300. The subject is very very complex. And to make it even more confusing the real world of 300 mph motorcycles is totally unexplored . For me I have to settle for the shape of the 250 ninja. I have done obvious things to smooth out the airflow. But I must look like a 250 ninja. If you don't mind . We should take this discussion to the Project X thread . This has gotten away from the Worldwide bearing conversation.
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March 22nd, 2016, 05:25 AM | #49 |
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Trans bearings
The trans bearings are simple to replace if you have the tools. And you have to split the case. So I guess not so simple. Once you have the transmission shafts out the front bearing slips on and off with ease. The rear shaft has a press on collar. This is between the bearing and the output sprocket. Before removing the engine you should remove the big nut and output sprocket. The sleeve will need to be pulled. There is no way to pry the sleeve off. Don't even try or you will damage things. The threads on te shaft are very fragile so I keep the bolt loosely attached most of the time. Using a gear puller or a bearing separator is the best way. Any auto shop will have these tools and not charge much to swap the bearing. Just pay attention to the bearing orentation. There is a clip that holds the bearing in the trans. These are half moon clips in the upper case half. Make sure there in place when you go together as they can stick to the old bearing and get lost. Then just reaassemble the engine acording to the manual.
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June 1st, 2017, 07:29 AM | #50 | |
The 2 Stroke Ninja!!
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June 1st, 2017, 08:55 AM | #51 |
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June 6th, 2017, 01:35 PM | #52 |
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I used the gold chrome spray paint. I first steamed the rims very clean and then broke the tires off the bead. But left them on the rim. Then taped up the tires. After that I mounted the rim/ tires in a wheel balancer and painted them while spinning them. That's it. Then just refill the tires.
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June 6th, 2017, 01:38 PM | #53 | |
The 2 Stroke Ninja!!
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June 6th, 2017, 01:40 PM | #54 |
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I don't know. It is the stuff you get at auto zone. Supposed to look like chrome but never does.
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June 6th, 2017, 01:42 PM | #55 |
The 2 Stroke Ninja!!
Name: Nick
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