twint78

im wondering who are some manufacturers that could custome make rotary bits.like rotors?housings?

i know where i could get an eshaft made

this is going to be for a unlimited gp bike me and some other ppl will be making.

i know brian at rotorsportsracing was going to have some company make custom light rotors and the first batch would of cost 20k.so he said no.

i would want to use renisis technology.basically multi side ports for intake and side port exhuast.

now as far as custom rotors would go i would want them really light and 20mm shorter so it would be under 990cc four stroke rules.i would use bunch of modifications to keep the engine reliable for a couple weekends as possible.hell it would probably go more than that.but it be rotating at a low 8k rpms when its in corners at slow speeds.

this bike would easily produce 250hp and 150 or so ft lbs of torque.and it would going against bikes idling at 2000 rpms and zipping all the way from 18k to 22k rpms.making only around 220hp to 240 hp with about 80 to 100 ft lbs of tq.

tia

protlewski

How do you figure it will produce that much power?

j9fd3s

iTrader: (3)

didnt someone say that jim downing cast his own rotors?

mike

Scalliwag

The 20k that Brian was quoted would be pretty reasonable. There is a real good reason why the first batch would cost so much. The casting molds would have to be created and bugs worked out. Then there is a lot of machine shop bugs to be worked out as well.
Casting custom rotors and housings will not be cheap.

The only way to get down the cost per unit is by producing large volume. The only way to produce a large volume and actually sell it is to create a product with appeal to a large number of people.
You would be better served to create side housings first and pattern the design in a way that they could be used in a 13b.
If you succeeded in creating side housings with "Renesis" type porting you could use stock rotor housings with block offs on the exhaust port.
The block offs could be made very easily by pulling the exhaust sleeve and casting a solid exhaust sleeve (a plug) and installing the plug in it's place. Below is a picture from a thread that I showed how to remove the roll pins to pull the sleeves out. Here is a link to the thread https://www.rx7club.com/forum/showth...hreadid=123225

But the bottom line is that if you are planning on having machined and/or complex parts made it will be expensive and unless you have unlimited resources you should try to make components that would attract the largest sales volume to start with and set aside a profit percentage to invest in R&D for other components.

twint78

yeah i know its pretty reasonable.i figured he would say no cuz 20k reasonable or not is stil 20k...alot.hehe.

but this would not be a 1 yr project this would a multi yr project with much r an d and time.

i think this project and type of bike would be awesome.and literally destroy ur unlimited bikes.think a bike that could easily put out this much power and still not need a rebuild for a few races or even more.as where there engines would need one after every weekend race.

also i like how the water jacket was pulled back in the renisis engine so its not hit and rubbed everytime u go into higher rpms.

im thinkin what ill do is start with a 2nd gen engine and use it for some measurements.pull 20mm off of each rotor and so on.i think this might be set a new foothold in racing motorcycle racing.