watch a noob build and race a land speed racing bike

[dave c]

copy n paste from my other forum were i have a couple lsr bike guys helping me build this

im going to say this now i have never modified a bike like this before

the inspiration 04 wr450f turned turbo lsr bike
http://i76.photobucket.com/albums/j39/lethalrides2k3/Turbo-Yamaha-Salt-Flat-Racer-by-Super-Rat_zps5xiwvkaz.jpg

im starting with a street legal 1986 honda xl250r
the turbo is a rhb31 good for 100 hp and is about perfectly sized for a 250cc engine
heres a small mockup before i decided to build a lsr bike
http://i76.photobucket.com/albums/j39/lethalrides2k3/IMAG0577_zpsoy3ftvzw.jpg

so far im still in the planning stages , and just today started to get serious about building this

http://i.imgur.com/hhT9Fy2.jpg

and from here im going to just copy and past my post from the other forum

ok so heres were were at as u can see above the rear suspension lowers beautifully
some how i missed the step in my forks tubes si i couldnt drop the clamps all that far but i may not have to

u can see the step here
http://i.imgur.com/tmYUsyu.jpg
i was able to drop the clamps one inch
http://i.imgur.com/ByJCUm2.jpg

i can bore out the top clamp to go over the first step though if needed for about another 2.75 inches of drop but i really need a wheel and tire to figure that out as a 17 inch wheel will drop the front an additional 2.125 inches


centerline of the rear axle
http://i.imgur.com/CfO9Q5G.jpg

centerline of the front axle with the 21 inch wheel
http://i.imgur.com/c1sgQEU.jpg

and from the rear footpeg mount ( lower craddle tube centerline ) is 7.25 inch from the ground
http://i.imgur.com/zlVK6Rs.jpg

the front centerline of the same tube is 8.75 inches from the ground so a 2 inch drop at the front axle centerline should even the lower craddle tubes to almost paralell to the ground
http://i.imgur.com/UfTe0W8.jpg

bike deff needs a bunch of stretch for me to get on it comfotably in a layed over position
http://i.imgur.com/4Nrf2qp.jpg

im thinking + 8 inches on the swingarm
http://i76.photobucket.com/albums/j39/lethalrides2k3/HD0060_zpsc3fhjoqd.jpg
and then cutting the rear subframe off tot he left of the right line and building my own , this will alow me to move the seat way back and let me lower the bike even more if i want to
http://i76.photobucket.com/albums/j39/lethalrides2k3/HD0060_zpscbz1zadc.jpg

the record for the class i am building for is currently 123.xx mph , something this engine combo should be capable of

[dave c]

http://i.imgur.com/LjH4Roj.jpg

notice anything wrong with this clutch stack ? this is how i pulled it out of the basket , had just a lil bit of clutch slip all last year lol
http://i.imgur.com/4Q640Ut.jpg

side shot of the clutch side of the engine
http://i.imgur.com/IeTmnYn.jpg
how the clutch stack should be , im going to end up turning my own bottom plate for the clutch stack so i can run a few more clutch discs
http://i.imgur.com/AbU6wod.jpg
and the twin carbs im doing blow threw on , going to try running this on e85 , or methanol of i can get jets big enough
http://i.imgur.com/GtprFIp.jpg
piliot jet is removed from the primary carb already secondary carb only has a main jet
http://i.imgur.com/ZYXQE3V.jpg

[dave c]

gentelmen we have extension , or atleast a temporay one for mockup
http://i.imgur.com/RZWLUhu.jpg
http://i.imgur.com/niNpIRn.jpg

lol couple changes to the suspension and i can do lsr/drag, and hill climbs lol
so heres how im thinking about dong the rear section of the bike , red lines are what im adding , and blue line at the back is just an extension of whats already there so i can move the seat and fender back
tieing all in to the swingarm should take all the flex out of the frame since im doing a rigid rear suspension

http://i.imgur.com/PPCyJvr.jpg

[dave c]

mocked up some more stuff today
http://i.imgur.com/vaOddrt.jpg

http://i.imgur.com/XoIN2mp.jpg

im going to possibly slide the battery forward and that leaves me enough room infront of the rear tire to build the fuel tank instead of putting the tank uptop on the top tube , not sure were im going to put it yet though

http://i.imgur.com/O6TwZtl.jpg

http://i.imgur.com/OykDRpZ.jpg

[nanoprobe]

notice anything wrong with this clutch stack ? this is how i pulled it out of the basket , had just a lil bit of clutch slip all last year lol
http://i.imgur.com/4Q640Ut.jpg

Hmmm? Looks like there is a plate missing. :rolleyes:

[dave c]

Hmmm? Looks like there is a plate missing. :rolleyes:

plates not missing , one of those dbl stacked frictions should have been on the bottom of the stack
the stack should start with a friction disc , and end with a friction disc

[nanoprobe]

plates not missing , one of those dbl stacked frictions should have been on the bottom of the stack
the stack should start with a friction disc , and end with a friction disc

I knew that. =))

[dave c]

quick update i picked up 2 motors one is another stock 86 honda rfvc 250 and i also got a yahmaha 550cc 4 cyl to play with , the yahmaha is for later though
ive had my cyl head flowed , and we ran some engine simulations with alcohol as the fuel and the rhb31 turbo@ 25 pounds of boost, shows it should make around 93 hp at 8,500 rpms that is as long as the engine itself doesnt turn into a grenade

soon as the new motor gets here im going to get it assembled on a stock frame witht he turbo system and take the bike out to a dyno to see what it puts down at the tire

i forgot to mention in order to get the clutch to hold the power we have to use valve springs off a small block chevy to get enough spring presure to clamp the clutch plates together