longer 5th gear and a new 2nd

[one2dmax]

No one makes a "bore" kit but there are plenty of options from engine builders like myself and others. Largest you can take the stock sleeves is 1275 (78.5mm). You can go as large as 1570 with custom sleeves (I have one 1570 chaindrive block on hand). 1500 is a decent compromise and makes excellent power but dependability is greatly reduced most of the time.

I do 1300 conversions since they are good power increase and very dependable. I imagine I can bore them out a bit as well to close to 1400 but would need to measure and make sure there is enough sleeve.

Sean

 

[naughtyG]

hi,

I might be interested in the 5th gear overdrive mod - is this something I could do myself, and if so where would I get the part(s) from, or would it be better to send my tranny to you (morley's muscle) for a straight swap? My bike's an '86 (aka as 'muscle bagger') and has no engine mods or problems that I know of.

Thanks,

nG

 

[one2dmax]

It's not a direct bolt in and requires undercutting of the dogs to match. You could simpl buy the 2 needed gears and have those and the mating gears cut but by that time you should just go ahead and do the whole transmission. I charge $800 for an undercut trans with overdrive and can do one on an exchange or you can send yours in for the work. right now they are only a few weeks out plus shipping time.

Sean

 

[naughtyG]

Thanks Sean, as soon as I get the time to get it out and funds for the works I will be in touch. I have a lot of 90 miles either way commuting coming up so I definitely want that overdrive!
Do you usually have a bunch of trannies ready for an exchange, or is it best to send mine in?

cheers,

nG

 

[one2dmax]

I have a number of transmissions on hand to send in but it is best a lot of times for me if you aren't in a hurry to send yours in. You at least know what you had that way too.

Sean

 

[ssnsltd]

not trying to -jack the thread:
"60 = 3000 80 = 4000 100 = 5000"


I am running that/those RPM with an 18" rear and the venture/royal final drive installed. would the 5th gear addition be too much ?

I am really happy with the change. the new tire and final drive gave me.

 

[one2dmax]

Rick Rash is running the overdrive as well as the venture rear diff. He's got a 1500 though so it makes enough power to pull it anywhere and anytime he wants.

I've had similar setups and I think you may want to check your rpm's vs speed again. I don't think you're totally accurate saying that your fifth gear with 18" wheel/tire and venture reqar diff are going to drop your rpm's that much.

Sean

 

[ssnsltd]

Rick Rash is running the overdrive as well as the venture rear diff. He's got a 1500 though so it makes enough power to pull it anywhere and anytime he wants.

I've had similar setups and I think you may want to check your rpm's vs speed again. I don't think you're totally accurate saying that your fifth gear with 18" wheel/tire and venture reqar diff are going to drop your rpm's that much.

Sean

thanks Sean,

I do have a 120/18/90 front tire, it was on the bike when I got it. guess that is a ~2% higher/taller tire:ummm:

the RPM stock, at 55 in 5th gear was 3500. after venture drive and ME880 180/55/18 tire is 3000. my 4th gear is now 3500 at 55.

at least that is what the gauge shows, it is small, I am old , and it is not digital, so I could be wrong .
thanks again!

 

[one2dmax]

I just rode one of the last bikes we finished up. He has 170/80/15 metz rear tire with stock matching front. Also has the venture diff. speed vs rpm:
60mph - 3500 rpm
70mph - 4000 rpm
80mph - 4500 rpm
90mph - 5000 rpm
100mph - 5500rpm

This is close to what you would have with the overdrive fifth with a stock rear tire but still 500 rpm's higher. With a taller tire like is on this bike the difference is even more.

Sean

 

[forestdaledave]

That fifth gear mod sure seems like a good idea. I'm always tring to find another gear while cruising. When cruising down the hwy I adjust my speed to just below when the vboost opens so it might be a receipe for tickets. lol
Dave #3505