Some advice and suggestions

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#1

Here is something that I am currently working on, it is a airbox for my bike. What I have done is make a rough form out of paper mache for simplicity. I want to make a copy out of glass and poly to keep it cheap, probably easiest for me to do as a wet layu up vs infusion.
Currently my thoughts are like this.

1 finish the final shaping
2 paint on by brush a couple layers of resin to make it stiffer and a bit harder
3 cover the entire resin coated mold with packing tape
4 wet lay glass onto the tape (since the resin does not adhear to the tape and also the tight crevices and curves would make polishing a bitch)
5 when the lay up is cured, remove the mold and newly formed part (if the resin does adhear to the mold I guess the original paper mache mold could be sacrificed without worry since I would have a better glass male form to work with)
6 buff and polish the new male glass form and do another lay up on the outside of that

Any ideas and suggestions, I am looking to keep this quick, cheap, and functional not necessairly pretty. Thanks

#2

The easy way to do this would be to lay the air box up over a foam core, and when its hardened dissolve the foam with acetone.

Have to ask though, if this is a modern sports bike what are you going to gain by making something like this? The std box is likely to work very well as it is, and not much you can do is going to improve it.

#3

Thats a really good idea, I could seal the paper airbox and cover all the holes and then pour in a liquid foam and allow it to expand and harden and then lay the glasss on top of that.

But what do you suggest for a foam? There are expanding foams that come out of a spray can, available form the hardware store that are used as insulating around crevaces. probably not the best wya huh?

the RC51 is a 1000cc vtwin and has a stock 7 liter airbox. It has been identified as a limiting factor of the bike in terms of performance, large gains have been noted with larger airboxes, www.honda-rc51.de has made one very similar to this, it is where I got the idea.

#4

Increasing volume of airbox may well mean increases in performance would be possible, if this was done in conjunction with other changes. However fitting a larger airbox alone. is likely to mean very small gains, which are very likely to be so small it would be very difficult to detect them.

In common with all modern sports bikes, there is far more to be gained by careful optimisation session on a dyno, than changing parts with no real idea of what works with what, and of course the final result that you are hoping to achieve.

Finally if you want to go head with an airbox, then I would use PU foam sheet, glued together to form the approximate shape you are looking for, then shape to exactly what you want, and then use as mould tool to laminate over. However remember the final foam shape needs to be slightly smaller than the moulding you are looking for. Personally I would make something like this out of aluminuim, rather than messing around with glass.