Kawi2strokes.com Forum

I've done all the bikes so far in Solidworks. I also have NX7.5 which I don't get along with well at all but Ford and a lot of automakers use it so they insist that it be the official university software. I'm also learning how to use Creo Elements/Pro E which I'll be using for work this summer.

Regarding FEA I've tried to FEA my trellis frame however I've not been able to get the mesh to generate correctly. I've had a lot of problems with the weld joints. The other part that bothers me about FEA is that you really need to validate the results somehow. In the case of a frame you would have to make a fixture apply a load to it and measure the amount it has moved with strain gauges. That is fairly challenging to do accurately. Plus what value would be perceived as correct? All frames should have some flex to them but so far no one really knows the correct amount or range. I've done FEA on individual components with more success so in that regard I think it is good and accurate. I'm not saying an entire frame isn't possible because it is, I just didn't see it as being all that beneficial to me. As for the amount of flex my frame has I know it is stiff which is what you want in a race bike. It may be an eternity before I'm a good enough rider to tell you if it it is too stiff or not.

I saw you did FEA on a braced headstock compared to a stock one. How did those results turn out for you? In the case of the triples I can see it being a bit easier and more useful since the frames are fairly flexible by nature so you could be certain that any stiffening you do would be beneficial.

Ha, those are MotoGP lean angles! I make no claims of being that good on a bike so if I'm ever in that situation I may already be in a low side!

When reading about such lean angles I'm always reminded of the late Volker Rauch's famous photo of Mike Hailwood taken from the rear in 1966 or 1967. Mike was riding a H@part number*a six, either the RC166/167 or RC174. He was at a phenomenal lean angle, but on Dunlop Triangulars, not today's supersticky and superwide slicks. The rear tyre was probably a 3.00 x 18, front at best a 2.75 x 18.

My problen was I never had an issue with the handling so difficult to fix something that isn't broke! For the most part, I did it to see where the bracing was effective and where it wasn't really required. The funny part was finding the most effective area to brace to reduce the deflection, (the head stock) was considered not required by a road racer here so go figure???

To be honest, the best way to verify your results is by just grabbing something you have in the shop like an i-beam or something smaller support it on each end with cylinders and put a weight in the middle... In theory, if you can get accurate results with something simple, you will get accurate results with something complex.
If you are having issues with multi bodies meshing, try making the model out of one piece, it should go much easier.
I was lucky enough to previously work at a company that had the full blown Cosmos but now I only have the basic version of Solidworks so I have to be happy with Simulationxpress... Pretty basic program as you know but still better then a kick in the pants...lol

At any rate, you have some pretty impressive looking models! Nice to see someone going through the process from start to finish!

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http://kawatriple.com/wtf/

I have thought the same thing as far as trying something simple goes but I'm a little skeptical. The more I use it the more I will trust it though so in time I will probably begin to rely on it heavily. I've actually used that method to try and validate some Flow Simulation results and SW was pretty much on the money with the simple CFD.

I thought of converting the frame to one piece but that would have been a lot of work! I chose to use a different material for the filler rod than the tubing as well so that may have thrown the results off too. At the end I decided that getting the results wasn't worth the effort. People have been building custom race bike frames long before FEA so I figured at my level of racing it is not all that important as long as a little common sense is used in the design.

A little trick for you for converting multi-body assembly into one solid part for FEA purposes...
Add a part to your assembly, a big brick that covers the whole frame, then use a mold feature called cavity and use all the existing components of your fame to create the cavity. The next step is to create another part and using the previous part you made as the cavity for this part. What you end up with is a facimally of your frame assembly but in one solid part.
Btw, don't get too concerned with weld material being different then base material... They will have similar modulus of elastistities and you are only trying to keep max stress below a certain point, which has nothing to do with type of material.
Also, You're best is to look at the strain graph to see where the l
defecting is actually happening... It's the best way to determine where beefing up is necessary.

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http://kawatriple.com/wtf/

It will be interesting, as I know of a few guys that tried the big 500's in road racing, and none could ride the things for the vibration. Can't wait for a rider report!

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Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........

Thanks for the tip, that is an interesting way of doing it. By converting it to a solid would it not FEA a lot differently than the tubular part? Maybe I'm being daft but I would've thought that there wouldn't be much correlation between the two? Especially if different thickness and sizes of tubing were used. Please explain further how that would work, I might be missing something. Also, good point on the weld material not mattering much.

My thought to get around the problem would be to save the part as an .igs file and then open it back up in Solidworks. All the features would no longer be recognized which I think is the main problem it's not meshing correctly. I've not tried it yet though so I'm not certain.

I was concerned about vibes too but I'm not sure if they will be as much of a problem as I thought. I took a lot of weight out of the top end which favorably changes the balance factor for a high revving single so it should be much improved over stock. I also machined the flywheels true as they were out .003" from the factory which will help a little too. I was able to true the crank to around .0005" as well. As you said we'll know how it vibes once I've ridden it. I ran the engine in my dirt bike frame and rode it a little bit and it was considerably smoother than my stock KX500 engine.

I found this 550 single the other day which I thought was interesting...
http://forums.everything2stroke.com/sho ... hp?t=32326

This site makes a complete fuel injection kit for 125 to 500cc 2 strokes. Cost is around $1350. They can also make controllers for twins, triples and four cylinder engines. I just stripped the complete injection system off of an '11 ZX6 and am waiting to hear back from them on the triple controller so I can try and run it on the 500 this year.

http://www.highgaintuning.com/category_s/59.htm