2nd gear issue and Gearing

[ryanschoebel]

Hey all, its been a few months since I've posted, I've just been lurking in the background. I had a question, my 84 has the second gear issue, and its currently geared up from stock.I was wondering, if I went back to stock gearing, or even down a tooth, would the extra torque exacerbate the second gear issue, causing it to jump more?

In other new, in the last few months, I have done a lot of maintenance, a few minor mods, rejetted the carbs on my own, and passed 50,000 miles. The bike still runs great, and since the rejetting, it feels much better than it did. Still loving this bike!!

[Pat Conlon]

Hi Ryan, good to hear from you....
You are not adding or subtracting torque, by changes to your sprockets. Engine torque is, what it is.
However, you are moving the peak torque RPM range up or down the road speed scale with the sprocket changes.
Stay away (far away) from the FJ engine's peak torque output with a dodgy 2nd gear.
With 18/40 gearing that peak torque will occur at a faster road speed
With the '84's oem 17/42 gearing, that peak will occur at a lower road speed.

So....at what RPM does the FJ1100 engine peak torque occur?  (64 ft.lbs at 8,000rpm)
https://www.motorcyclespecs.co.za/model/yamaha/yamaha_fj1100%2084.htm

Just short shift around 2nd gear until you get a undercut gear set and 3 new shift forks from Randy

http://rpmracingca.com/proddetail.asp?prod=UCT

Install the RPM roller shift kit while you're in there:
http://rpmracingca.com/proddetail.asp?prod=RPMRollerShiftkit

You will be a very happy man with this ^^ combination. Ask me how I know...

Snick, snick...hold on, here comes the kookalooooooooo!

[Millietant]

You're the first person I've seen on a bike forum say that shortening the gearing doesn't affect the torque the bike produces Pat.......and thank goodness for that, I thought I was the only one who thought that !!!  

Ryan - listen to Pat, his advice is good. Ride around the problem by minimising the use of 2nd gear and by using light throttle, low revs and short shifting when you do have to use 2nd gear (the FJ has more than enough torque to allow you to ride like that easily) until you can get the parts from RPM and do the repair with improved parts, so it never happens again.  

[Mike Ramos]

Hi Ryan, good to hear from you....
You are not adding or subtracting torque, by changes to your sprockets. Engine torque is, what it is.
However, you are moving the peak torque RPM range up or down the road speed scale with the sprocket changes.
Stay away (far away) from the FJ engine's peak torque output with a dodgy 2nd gear.
With 18/40 gearing that peak torque will occur at a faster road speed
With the '84's oem 17/42 gearing, that peak will occur at a lower road speed.

So....at what RPM does the FJ1100 engine peak torque occur?  (64 ft.lbs at 8,000rpm)
https://www.motorcyclespecs.co.za/model/yamaha/yamaha_fj1100%2084.htm

Just short shift around 2nd gear until you get a undercut gear set and 3 new shift forks from Randy

http://rpmracingca.com/proddetail.asp?prod=UCT

Install the RPM roller shift kit while you're in there:
http://rpmracingca.com/proddetail.asp?prod=RPMRollerShiftkit

You will be a very happy man with this ^^ combination. Ask me how I know...

Snick, snick...hold on, here comes the kookalooooooooo!

Hey Ryan!

Listen to the old fella (!) he knows of what he speaks...!

After many miles on two different FJ's with stock transmissions, there is a HUGE improvement with the undercut gears.  It really improves the quality of the ride...  well worth the investment.

Ride safe,

Midget