first step of new build

[dsrace]

ok guys I sold my v-6 rail yesterday and am going back to mc rail. I want to try a different idea and am looking at the yamaha v-max 1.7 ltre or 1697 cc engine. I'm thinking of coupling it to a bmw rear diff since it's shaft driven. the bmw rear diff's have several r&p combo to choose from stock. the primary and secondary reduction are done in the case on the v-max because it's shaft driven. i'm trying to figure which r&p to go with for a 1200 lb rail on 1300 paddles. I would like to turbo this engine as well. here are some specs on the engine and trans.


a thanks to yummi for helping with the info!


ENGINE

Type:  Liquid cooled, 4-stroke, DOHC, 4-valve, V-type 4-cyclinder
Displacement:  1,679cc
Bore & stroke:  90.0 x 66.0 mm
Compression Ratio:  11.3:1
Max. power:  147.2 kW (200 PS) @ 9,000 rpm
Max. torque:  166.8 Nm (17.0 kg-m) @ 6,500 rpm
Lubrication:  Wet sump
Carburettor / Fuel supply: Fuel injection
Clutch type:  Wet, multiple-disc diaphragm spring
Ignition:  T.C.I.
Starter system:  Electric
Transmission:  Constant mesh, 5-speed
Final transmission:  Shaft drive
Primary reduction ratio: 1.509
Secondary reduction ratio:  3.082
Gear ratio: 

    Gear ratio-1st gear:  2.375
    Gear ratio-2nd gear:  1.810
    Gear ratio-3rd gear:  1.400
    Gear ratio-4th gear:  1.115
    Gear ratio-5th gear:  0.935

http://www.holeshot.com/dynocharts/dyno_09vmax_fx.html


here are some spec on the busa to compare it to.

http://www.aperaceparts.com/tech/specshayabusa.html

I know from enemy's rail that 4.86-1 final drive ratio works very well in the sand running 1100 paddles, my 1300's are 1" taller and of course 2" wider. the rails should be very close in weight. that 4.86 is after primary reduction.

2-1 r&p any thought's? aslo clutch type, which would be less prone to slipping?

this is just a thought right now and I can't seem to find any wrecked bikes for donars as of yet either.

[dsrace]

If i can make this happen i was thinking of trying to couple this rev unit to the input of the bmw diff.

http://www.quaife.co.uk/shop/products/qba7r

[Nutz4sand]

I have not held one in my hands but I have heard the Quiafe unit has play or slop in it (I am not sure of this or see how it could)

So check that out before you go for it.

Yoshi has a similiar unit that was less loot and supposed to be good for crazy power but I cannot recall the maker of it at this moment. 

[dsrace]

thanks nuts I'll have to look into that when the time comes.

[Carlriddle]

1st step-I'd say you've done that 

And those motors are rare as virgin hooker.

Looks like Enemy is running 20:1 total reduction in 1st gear.  And for that motor to be similar looks like a diff in the 1.81:1 range.  Didnt realize those had secondary redution too, so the shaft is 1:1 at rear wheel? 

Here's an inline rev, uses th400 splines 12" long and rated to 500hp. http://www.roadstercycle.com/

[dsrace]

ya I am finding out old people must own them cause I can't find any wrecked ones! did find a few with 60k miles on them! damn they must not stay home   

I have seen that inline rev unit but thanks for posting it. I really am not to worried about rev to be honest but i say that now and maybe not later.

[BDKW1]

That motor is as bad ass as it is rare......... I've been looking for a salvage one for a couple of years.

Jeffco also makes an inline reverse box.

Beemer diff........ Sounds expensive to change the R&P. An 8.8 out of Mustang is all aluminum and pretty cheap to regear. Plus the are many options for diffs from spools to Torsen types.

[dsrace]

thanks for the info. I will look into the mustang if I can find one of those motors but it's not looking good right now. I put a couple call into a 2 salvage companies I have done business with in the past, we'll see what they can come up with. otherwise I will just go with the busa.

[BDKW1]

T-birds had cast units which a cheaper and easier to find, just heavier. I think the Newer exploders came with alum ones too. If you need it to spin the other direction, newer F150 front diff's are reverse cut 8.8's..........

[Engineer]

1st step-I'd say you've done that 

And those motors are rare as virgin hooker.

Looks like Enemy is running 20:1 total reduction in 1st gear.  And for that motor to be similar looks like a diff in the 1.81:1 range.  Didnt realize those had secondary redution too, so the shaft is 1:1 at rear wheel? 

Here's an inline rev, uses th400 splines 12" long and rated to 500hp. http://www.roadstercycle.com/

I think that the 3.08 secondary reduction is between the shaft and the rear wheel, so that will be eliminated.

I come up with needing a 1:5.5 to be around 20:1 in first gear.  The red line is much lower on this motor than the busa so it may be OK with less reduction.

Based on 31" tall tires I come up with a 1:5.88 ratio needed to put the 9K red line at 100 MPH.

[Carlriddle]

Engineer is correct  secondary redution at rear wheel. 

http://www.bikebandit.com/houseofmotorcycles/2009-yamaha-v-max-black-metallic-m-vmx17yb/o/m18185#sch595462

But that makes it a little easier on the diff ratio.  Theres a company called Madmax that does all sorts of mods; chain conv, fat tire, turbo, and supercharger. 

[dsrace]

thanks guys!   ya i forgot about the r&p at the wheel , getting old I guess. 5.88 or 5.5 would work really and I like to think of this combo as this old man's motorcycle rail.  between the v-6 rail and bike more grunt less rpm for the old guys    . where enemy is running that 1100 paddle I have a set of 1300 of the same brand I want to run cause I already have them!!

engineer I really am not worried about hitting 100 mph anymore and factory rev limits are always set low 

BDKW1  you think they offer a 5.5 -1 5.88-1 r&p for that mustang rear diff? I know in the bmw 318i deepest stock was 4.45 with lsd and $400 used.

[dsrace]

well if I can't find a wrecked v-max I will just go busa and give one of these units a try, maybe.


http://www.lynxae.co.uk/Products-Bikesports.htm

[BDKW1]

They make a 5.13, 5.71 and a 6.14. These are for the SUV rears. The cars ones only go to 4.11 for some reason. Not sure if there are differences in the cases or if they just don't think a passenger car would ever need anything deeper than a 4.11

https://www.ringpinion.com/b2c/PartsList.aspx?SearchMode=Diff&TypeID=4&DiffID=166&CatID=35

[dsrace]

thanks for the link .