An Idea for having the a fifth gear overdrive, Please tell me if it will work

[Yap Yap]

Ok so here is an idea for having the fifth gear as an over drive gear for high speed cruising,

what would happen if you get the gear pair for 1st gear, flip them, install them as 5th gear pair. I don't know if what I am saying makes sense but it should work as ratio between the gear pair that make 1st gear are bigger, so if you get an extra pair and flip them they should work as an over drive 5th gear?

Edited January 15, 2016 by Yap Yap

[seer]

Aren't the shafts different?

[seer]

You're not in to deep yet. Sure you don't want to step back for an exc or husky wr?

There's a Yamaha wr 200 for sale local. Plated.

[Yap Yap]

Shafts "look" the same. IDK

Trust me I am really deep in the project. I acquired all the parts and I expect to finish the project in 2 weeks max. I bought a car for commuting so no more commuting on a motorcycle. I just want to go fast when riding supermoto and I need a wider gearing or an over drive 5th. I know no one is going to answer my question.

[Yap Yap]

Yeah they seem to be different, they have a different number of teeth.

[jblob]

How big is the ratio difference between the current 5th and a reversed 1st set? 

What bike is this going to be on? Looks like you are selling your crf230

Sometimes gears can be switched out or removed but I can't tell you for sure if it will work. You are in fairly uncharted territory but if you have the time why not try. 

[Yap Yap]

How big is the ratio difference between the current 5th and a reversed 1st set? 

What bike is this going to be on? Looks like you are selling your crf230

Sometimes gears can be switched out or removed but I can't tell you for sure if it will work. You are in fairly uncharted territory but if you have the time why not try. 

it's a big difference, I found this excel sheet. I would give credit to who made it but I don't have his name.

Ratio for first gear is  1.800, if you flip it then the ratio will be 1/1.800= 0.556

Here is the graph or rpm/speed. Notice gearbox functions normally and stays in the power band until 60mph, now you shift to over drive where you can cruise at 5000-6000 rpm going 70mph

Edited January 16, 2016 by Yap Yap

[jblob]

That is a heck of a deep overdrive gear, it would pull more slowly up to 70 than it did the rest of the gears.

Are you planning to make it street legal? I saw you mention supermoto which would make that gearing suck any time you hit 5th you would lose a lot of acceleration, but top speed would increase considerably, would just take longer to get there which is fine on the highway when you arent (or better not be) racing.

I have a plated xr100 that he been on the freeway many times mostly in heavy traffic but when traffic is light ask me how I know about having the wrong gearing! 

[Yap Yap]

That is a heck of a deep overdrive gear, it would pull more slowly up to 70 than it did the rest of the gears.

Are you planning to make it street legal? I saw you mention supermoto which would make that gearing suck any time you hit 5th you would lose a lot of acceleration, but top speed would increase considerably, would just take longer to get there which is fine on the highway when you arent (or better not be) racing.

I have a plated xr100 that he been on the freeway many times mostly in heavy traffic but when traffic is light ask me how I know about having the wrong gearing! 

Oh no racing after 4th gear haha. just to get home on the road without high rpm, 5000 at 60 mph is perfect. if you want to go fast you can go fast till you hit 60, after that you ride in your 'chill' 5th gear. I still think 2 counter shaft sprockets swapping is easier.

If you want a less deep 5th, you can swap in the second gear pair, but I think the driver-driven on second gear is different than 5th.