Motorcycle sprocket material?

[JackD]

There is no Gandon, Oregun.
  97411 is Bandon, OR.
Probably just a typo.

You have to excusr Freud, he is old.  LOL

[narider]

350- cc motorcycle -  70 HP

Steel fronts and 7075 drilled aluminum rears, in a 520 series. If it's not already, your existing steel front(525 or 530) sprockets can be ground to fit a 520 chain.
And I agree, PBI first choice(I think they're owned by Chris Products now though 503-645-6500 ), then Sprocket Specialists 2nd(they're both in Oregon).
Todd

[Super Kaz]

Kosman Specialties made me a Nice 30T to go with my 24T Front=?speed @ 10000rpm My Math is bad also so maybe one of the Physicist on the Board can tell me ? What Top speed my gearing would be capable of on my Turbo V-rod if I could pull it to 10k?

[Speed Limit 1000]

You also need the tire diameter to get the speed

[Sumner]

You also need the tire diameter to get the speed

Plus the primary drive ratio and the final gear box ratio.

Go here:

http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html

and download one of the motorcycle spreadsheets depending on the number of gears you have and plug in the tire size, primay gear ratio, etc. and you will have what you want.

If you have problems with that let me know your Tire Diameter, Primary Drive Ratio, and 4th Gear ratio (if that is top gear) and I'll tell you how fast 10,000 rpm is in 4th.  If you want to know how fast 10,000 is in any other gear let me know that gear ratio.


c ya,

Sum

[Stan Back]

Maybe he's gonna run just the sprocket -- good traction potential, but probably illegal.

[Super Kaz]

You also need the tire diameter to get the speed

Plus the primary drive ratio and the final gear box ratio.

Go here:

http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html

and download one of the motorcycle spreadsheets depending on the number of gears you have and plug in the tire size, primay gear ratio, etc. and you will have what you want.

If you have problems with that let me know your Tire Diameter, Primary Drive Ratio, and 4th Gear ratio (if that is top gear) and I'll tell you how fast 10,000 rpm is in 4th.  If you want to know how fast 10,000 is in any other gear let me know that gear ratio.


c ya,

Sum

17in Kosman wheels with two of those 250mph motorcycle tires on it.
The Bike has a stock V-rod transmission with 5 gears. Don't know what 5th is,but can find out.
Thanks!

[Sumner]

17in Kosman wheels with two of those 250mph motorcycle tires on it.
The Bike has a stock V-rod transmission with 5 gears. Don't know what 5th is,but can find out.
Thanks!

I need the tire diameter not the wheel size.  Also your primary gear ratio from the crank to the transmission and the 5th gear ratio. 

Did you try and download the spreadsheet??

c ya,

Sum

[firemanjim]

Hey,Kaz.Try this one ,it has Vrod specs in it.
http://www.rbracing-rsr.com/gearspeed.html

[Super Kaz]

Hey,Kaz.Try this one ,it has Vrod specs in it.
http://www.rbracing-rsr.com/gearspeed.html

I tried and got this??

Drivetrain and Speed Calculator



  Definitions:

Your primary drive, transmission and rear drive sprockets all combine to determine your cruising rpm as well as your final top speed. This calculator will show you your speed in each gear from everything from a stock bike to an all out drag bike with a separate jackshaft as well as the one we love the most, the Bonneville racer. The big end is where it's at!

Engine RPM -- You can enter your final redline figure or any other rpm, say the rpm you want to cruise at for a given speed, and the calculator will help you figure out the transmission and sprockets you will need.
Primary Drive -- This can be the oem compensator sprocket which is connected by a double row chain to your clutch...or a belt primary which comes in a variety of pitches and widths. In any case, it's a front and rear sprocket of some sort. One end at the crankshaft and the other end going into the clutch/transmission.
Transmission -- Four speed early items, five speed later transmissions, aftermarket six speed gear sets, two speed and three speed planetaries, high gear only Pro Dragsters...there are lots of options out there. Enter your given ratios and see what your speeds are.
Jackshaft -- Some drag race bikes and some Bonneville designs will use a intermediary jackshaft either to gain an offset to clear a wide tire or to prevent a final drive chain from being "too long".
Diameter of the Rear Tire -- You need to know the height (diameter) of your rear tire when properly inflated.
Tire Growth -- At speed the tire will grow. For regular road tires the effect is neglible but for the larger drag racing slicks it is considerable. As the tire expands your final drive ratio changes. In effect the tire becomes a variable gear and part of your "transmission".
Wheelspin -- In drag racing and at Bonneville you are going to have a percentage of wheelspin you are going to have to plan for. This will depend on a lot of factors which have to be determined, mostly through experience. You will have to gear "taller" to achieve your desired trap speed. For drag racing with ultra high horsepower apps like our 113 ORCA Turbos this should be about 5%. For Bonneville where traction is a variable depending on salt conditions you may have to figure in 10%...i.e. rear wheel going 220, front wheel going 200.
 

1st 2nd 3rd 4th 5th 6th @RPM

 

Drivetrain and Speed Calculator

Engine RPM  rpm Enter your target RPM. This may be peak rpm at redline or any other rpm. If you plan your bike to cruise at a certain rpm band where your engine is smoothest or where your torque band is at some optimum point choose this to work out your gearing.
Front Primary  teeth OEM compensator sprocket or belt drive pulley. Early big twins 24 teeth. Late big twins 25 teeth. Sportster 35 teeth. V-Rod 64 teeth.
Rear Primary  teeth At your clutch basket. Early big twins 37 teeth. Late big twins 36 teeth. Sportster 56 teeth. V-Rod 117 teeth.
First Gear  :1 Ratio to One. Early 4 speed: 3.044; Big twin 96 up: 3.21; big twin 80-95: 3.24; Sportster: 4.30; Six-Speed 2.94 or 3.21 depending on make; V-Rod 2.51
Second Gear  :1 Ratio to One. Early 4 speed 1.820; Big twin 96 up: 2.21; big twin 80-95: 2.31; Sportster: 3.15; Six Speed: 2.08 depending on make; V-Rod 1.68
Third Gear  :1 Ratio to One. Early 4 speed: 1.227; Big twin 96 up: 1.57; big twin 80-95: 1.6; Sportster: 2.29; Six Speed: 1.53; V-Rod 1.34
Fourth Gear  :1 Ratio to One. Early 4 speed 1.000; Big twin 80 up: 1.23; Sportster: 1.88; Six Speed: 1.24; V-Rod 1.16
Fifth Gear  :1 Ratio to One. All models: 1; V-Rod 1.04
Sixth Gear  :1 Ratio to One: .86 or .89; Enter 1 if no sixth gear.
Jack Shaft In  teeth 1 if no jackshaft. Teeth on transmission output shaft if jackshaft is used.
Jack Shaft Out  teeth 1 if no jackshaft. Teeth on jackshaft if jackshaft is used.
Trans Pulley  teeth Typical big twin 32; 883 Sportster: 27; 1200 Sportster: 29; V-Rod 28 (Euro 30)
Rear Wheel Pulley  teeth Typical big twin: 70; 1998 Softail: 65; Big Twin Export Models 61 or 65; Sportster: 61; V-Rod 72
Rear Tire Diameter  inches 16" Street Tire: 25.75 (average); Drag Race Goodyear 29 or 31; 15" x 4.5" Goodyear Bonneville Tire (24.8; 25.4; 27. 
Tire Growth :1 1 for street tires. 1.1, 1.15, 1.2 etc. for drag race slicks that expand with rpm.
 
1st 2nd 3rd 4th 5th 6th @RPM

 




 
 24t front 30t rear"No PULLIES" and it came out 610mph in 5th WTF?? I'm not very good with number if I could gbet a little Help?

[ol38y]

First I want to thank Firemanjim for the link. I used it for a sportster I am building and it was a big help. The numbers were a little different then I had come up with, but it showed me I was in the ballpark. 
I'm gearing for 170 mph with 10% wheel spin at 7000 rpm. If any of the motorcycle guys see a problem here I'd appreciate any feedback...

I ran the numbers for the v-rod and came up with 335.23 mph. But, will a v-rod pull 10,000 rpm? The only variable I had was the tire size and I guessed at 25.75.
 

[JackD]

Consider in a bike transmission you are never going to be 1 to 1 and not going through the gears anyway.
Gear ratio selection to match all the variables you will encounter at the salt is sometimes the last thing you can do.
After you have decided what RPM and tune up serves you best, how to make yourself small, how to best hook it up, and a whole list of things you never thought about before, only then can you direct what attention you have left to gear selection.
The last shift into the gear you have selected is going to be at the point the bike sees the most load and if done wrong it can kill a lot of speed.
You have to decide did the last ratio jump with the shift drop the motor down to the point it takes too long to recover if at all.
You might find in a 5 speed for example the closest ratio is between 3rd and 4th .
If that is the case, you might consider fitting the sprockets to run 4th as your top speed gear.
For example if your combination is running WFO in 5th and when you drop down a gear it goes faster, that tells you something.
The 2%, 5%, 10 % slip is going to be a product of your package and nobody else.
It is something to consider and just another thing you can improve on.
What you learn at 100mph helps a lot to go over 300mph.
OH, did I mention it is better for your learning curve if you can make it last all week ?

[Dean Los Angeles]

The other factor in gear ratios is the power drop when you shift. I filled out all the data on the Drive Train and Speed Calculator for my TZ250.
1st gear worked out to 70.44 mph at 13,000 rpm. Once you fill out the data, change the rpm to the lowest rpm that you calculate is the start of the power curve. I did that and came up with 48.76 mph in 1st gear at 9,000 rpm.
This says that if I fully engage the clutch at any slower speed I'm going to bog the engine.
2nd gear worked out to 90.13 mph at 13,000 rpm. Since I was going 70.44 in 1st gear, that is the speed I will be going when I shift to 2nd gear. Adjusting the rpm to match 1st gear top speed in 2nd gear worked out to 10,200 rpm at 70.44 mph. This will tell you where in the power curve you are going to be when you shift, and give you an idea if those ratios will work out.

[Sumner]

First I want to thank Firemanjim for the link. I used it for a sportster I am building and it was a big help. The numbers were a little different then I had come up with, but it showed me I was in the ballpark. 
I'm gearing for 170 mph with 10% wheel spin at 7000 rpm. If any of the motorcycle guys see a problem here I'd appreciate any feedback...

I ran the numbers for the v-rod and came up with 335.23 mph. But, will a v-rod pull 10,000 rpm? The only variable I had was the tire size and I guessed at 25.75.
 

Using my ( spread sheet ) and  the 25.75 tire dia. and the rest of the gear ratios and primary drive off the other site I got 325 mph (I didn't adjust for tire growth or slippage) at 10,000 rpm.

The spread sheet shows if you shifted at 10,000 (seems very high to me for that type motor) the following:

1st --- 10,000 rpm --- 134 mph and will drop 3300 rpm going into 2nd
2nd --- 10,000 rpm --- 200 mph and will drop 2000 rpm going into 3rd
3rd --- 10,000 rpm --- 250 mph and will drop 1340 rpm going into 4th
4th --- 10,000 rpm --- 290 mph and will drop 1039 rpm going into 5th
5th --- 10,000 rpm --- 325 mph

Now without changing anything on the spread sheet you can look at a 7000 rpm red line and get the following:

1st --- 7000 rpm --- 93 mph and will drop 2325 rpm going into 2nd
2nd --- 7,000 rpm --- 140 mph and will drop 1421 rpm going into 3rd
3rd --- 7,000 rpm --- 175 mph and will drop 940 rpm going into 4th
4th --- 7,000 rpm --- 205 mph and will drop 734 rpm going into 5th
5th --- 7,000 rpm --- 226 mph

I realize using my spread sheet might not be as easy at first as the other on-line calculators, but once you do you will see you have all of the important info (what JackD is talking about) right in front of you and you can print it out and change just one thing at a time and see immediately how it effects all of the gear changes.  Most importantly the rpm drop that lets you see if you are falling out of the power band.

Try it and I think you will like it.  If you don't know how to load a spreadsheet get someone to help you the first time. Pretty soon you will be making your own and these can be as important tuning as anything in your tool box.  That also goes for you car guys.  I have them for 3 speeds through 6 speeds and sometime in the future I'll add a place to put in an intermediate jack-shaft ratio and also a place to put in a factor for tire growth and slippage if someone wants that too.

c ya,

Sum

[JackD]

The AMO kid from Dakota has my pocket sized Super Calc.
 that has all that stuff in it and lots more.