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final gearing

Started by Cash Dereszynski, December 29, 2014, 11:22:58 PM

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Cash Dereszynski

Whats the opinions on 17/43 sprockets?
Too high to use it for anything except drag racing?

Cash
Fuck it,let's ride.

FJmonkey

Quote from: Cash Dereszynski on December 29, 2014, 11:22:58 PM
Whats the opinions on 17/43 sprockets?
Too high to use it for anything except drag racing?

Cash

Lets try this from a different angle...

What are you looking for? What do you have?

I like the taller gearing, less punch when I twist the throttle but more high end speed. I run 18/38...

:unknown:
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

TexasDave

Search the files. There are as many opinons on gearing as there is on what oil to use. Stock gearing on the 84 FJ is 17/42. I ran mine with that gearing in town and highway and it was fine. Since most of my riding is highway speeds I went to a 18/42 to bring down the rpm's. It depends on what kind of riding you do most.  Dave  
A pistol is like a parachute, if you need one and don't have one you will never need one again.

FJmonkey

The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

movenon

Quote from: Cash Dereszynski on December 29, 2014, 11:22:58 PM
Whats the opinions on 17/43 sprockets?
Too high to use it for anything except drag racing?

Cash

You need to ride it for a while to get a feel for what is right for you.  Your combo as stated will be pretty low and you will like it around town but on the freeway you might want a higher ratio.  It's all a personal as to what you want.  I started at stock went to 18/38 and the dropped the front to 17.  I am happy with 17/38.

I might be off here a little but one tooth on the front is equal to about 3 teeth on the rear. I am sure someone has the exact ratio.

I will end it where I started, ride the thing before you make any decisions.  :good2:
George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

Mark Olson

Quote from: Cash Dereszynski on December 29, 2014, 11:22:58 PM
Whats the opinions on 17/43 sprockets?
Too high to use it for anything except drag racing?

Cash

My opinion is sounds like fun .  You are gonna give up some top end but have a lot more bottom end for climbing hills and steep grades.
You may experience minor front wheel lift on hard acceleration. If you are riding 2up with luggage this is the perfect combo to keep the fj snappy.
you will still have plenty of power for the freeway.

I currently run the 17/41 on my 86 and get 35 mpg if on the mains for extended periods, all freeway is 45mpg with an average of 38-40mpg for spirited riding.
120/70/17" on the front with a 180/55/17" on the rear. When on level ground I see 5k rpm for 80mph.

I did play around with gearing using a 17/45 =wheelie monster , tire smoker , got annoying with it lifting the front wheel accelerating out of a corner.
                                                       17/43= snappy and fun but found myself in the wrong gear (3rd )trying to exit corners (2nd would be redline for me).
                                                       17/41=My personal favorite , well balanced and in the right gear for the corners. good for 2up and bags.
                                                       18/38=bogged the whole bike down and lowered my fun factor. engine pinged ,did not like it.
                                                       18/41=I will use this setup for long distance runs between states , great mileage and still usable power.

I must state these are my opinions and YMMV (your mileage may vary).

Please use steel gears , the fj eats aluminum ones. 
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

FJ1100mjk

Q1: Be it either 18/41 or 17/41, is a chain length of 110 links good for each set of gearing?

Q2: I thought that I dug up an old post, and someone fitted a 18/42 set, and they could barely use a 110 link chain. I think they said that they had to take a rat-tail file (slightly) to the fronts of the axle slots on the chain adjusters to get that chain length to fit. Can anyone confirm?

Thanks.
Platinum Zircon-encrusted Gold Member

Iron Balls #00002175
www.ironballs.com


ZOA NOM

I'm running 18/43 on a 180/55 GSXR wheel and its growing on me. I like the oomph, and I'm getting 40mpg, no matter what.

edit: 110 link chain worked fine for me
Rick

Current:
2010 Honda VFR1200 DCT (Full Auto!)
1993 FJ/GSXR 1200 (-ABS)
1987 Porsche 911 Carrera (Race)
1988 Porsche Carrera (Street)
Previous:
1993 FJ1200 (FIREBALL)
1993 FJ1200ABS (RIP my collar bone)
1986 FZ750
1984 FJ600
1982 Seca

Mark Olson

Yes on the 110 link for that combo.
Mark O.
86 fj1200
sac ca.

                           " Get off your ass and Ride"

Pat Conlon

Pick a flavor. My fav is 18/40

The larger diameter 18 tooth counter shaft sprocket is easier on your chain.
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

TexasDave

Quote from: Pat Conlon on December 30, 2014, 06:17:07 PM
Pick a flavor. My fav is 18/40

The larger diameter 18 tooth counter shaft sprocket is easier on your chain.
I have been running 18/42 for the last 10,000 miles and going to install my 40t sprocket when I change the rear tire. I think that will do it for me at highway speeds of 75 to 80 to keep up with the cagers here in Texas at a reasonable rpm.  Dave
A pistol is like a parachute, if you need one and don't have one you will never need one again.

fj1289

Quote from: Cash Dereszynski on December 29, 2014, 11:22:58 PM
Whats the opinions on 17/43 sprockets?
Too high to use it for anything except drag racing?

Cash

Not at all - probably great in-town gearing or weekend fun gearing.   Want to do a road trip - then just swap in an 18 c/s sprocket. 
Now 16/43 starts to become heavily drag oriented, and maybe too much gear depending on your chassis setup...

ribbert

Quote from: Pat Conlon on December 30, 2014, 06:17:07 PM
Pick a flavor. My fav is 18/40

The larger diameter 18 tooth counter shaft sprocket is easier on your chain.

My last 2 sprocket sets have been 18/41 having previously run standard gearing. You do lose a little punch but it's a pretty good compromise.

Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

ribbert

Quote from: Mark Olson on December 30, 2014, 05:20:44 PM

.....When on level ground I see 5k rpm for 80mph.


....and on hills?  :biggrin:

Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

Dogsbestfriend

I ran 17/42 teeth with a 160x17 tyre and found it too short geared for comfortable riding, the engine felt far too busy and I had two vibration periods at inconvenient cruising speeds.  Went up to 18/42 teeth, back to almost like stock.
18/40 teeth with a 180x17 tyre, very similar.
18/40 teeth with a stock 150/80 x16 tyre is a nice cruising combination that still goes up hills.
The problem with short geared final drives is that the overlap of the gears gets reduced. Fine if you like stirring gears but for me the FJ works best with tall gears. It is a big CC engine so you can get a lot of fuel into it to compensate for any ill judged speed vs revs situation and it will still cope.
All of the above sprocket combination where done with the same chain which has a few thousand miles on it.