5th gear overdrive options

[Gravesdigger 2]

 I have searched the net looking for a way to (numerically) lower my gear ratio on my 99 Foreman 450. I have more than enough low end torque on tap but that's cause the engine starts to rev pretty high when past half throttle in 5th gear. Is there a way to change the ratio for 5th so it will be more of a overdrive? I'd like to be able to run the bike at dirt road speeds (40-45 mph) without the engine singing like a Formula one cart. If there's no changing 5th gears ratio, what about the axle's ring and pinion?  I've already gone up 2 sizes with my tires and I don't want the bike any taller than it already is now. Suggestions, advice, theories, w.a.g.'s and the like are welcome. 

[Goober 1,547]

99 Foreman full time 4wd?

40 - 45 mph? Awful fast there. Your speedo doesn’t account for your larger tires, so whatever it’s reading is gonna be low. 
 

do you want it to be a good mudder or a sporter?. I don’t know if there’s a good tweener.

[jeepwm69 6,601]

Oversized tires means your actual speed will be higher than what shows on your speedometer.

 

Only way I can see getting what you're after is having someone build you a new primary gear/ clutch basket set of gears.  I think a 300 primary and clutch basket will lower your gearing in the 450 like 15%, so you'd need something that does the opposite.

 

I'd live with it.  No Honda utility is going to go more than 40-45 without the engine screaming, because the only way to achieve that is to kill the low end gearing which is what you need with a utility ATV. 

 

If you need to go that fast, get you a sport quad for the roads LOL

[Gravesdigger 2]

I'm 45 years old. I've ran these same dirt roads sideways at 75 mph on a banshee wearing flip flops and shorts and was lucky enough to blow the engine before killing my foolish adolescent a$$. I've also tried to turn a Grizzlie into a submarine that'll cross any mud hole, stream, river, lake, ocean, etc. I did it. I enjoyed it. I outgrew it. I have a utility ATV that does everything I need or want to do which is mostly just hauling me from here to there and back. All I want to do is keep up with traffic without floating the valves. 

[shadetree 5,448]

On 11/15/2021 at 8:58 AM, jeepwm69 said:

Oversized tires means your actual speed will be higher than what shows on your speedometer.

 

Only way I can see getting what you're after is having someone build you a new primary gear/ clutch basket set of gears.  I think a 300 primary and clutch basket will lower your gearing in the 450 like 15%, so you'd need something that does the opposite.

 

I'd live with it.  No Honda utility is going to go more than 40-45 without the engine screaming, because the only way to achieve that is to kill the low end gearing which is what you need with a utility ATV. 

 

If you need to go that fast, get you a sport quad for the roads LOL

for the record, my stock '03 trx450fm, stock wheels and tires, HAS TOPPED OUT AT 49 ON A TWO LANE ROAD !.

[shadetree 5,448]

On 11/15/2021 at 6:35 AM, Gravesdigger said:

 I have searched the net looking for a way to (numerically) lower my gear ratio on my 99 Foreman 450. I have more than enough low end torque on tap but that's cause the engine starts to rev pretty high when past half throttle in 5th gear. Is there a way to change the ratio for 5th so it will be more of a overdrive? I'd like to be able to run the bike at dirt road speeds (40-45 mph) without the engine singing like a Formula one cart. If there's no changing 5th gears ratio, what about the axle's ring and pinion?  I've already gone up 2 sizes with my tires and I don't want the bike any taller than it already is now. Suggestions, advice, theories, w.a.g.'s and the like are welcome. 

utility atvs are not, were not made to set land speed records for the this, move up to sport quads, utility atvs will never do this. ( least not without deep pockets ! ).

[Fishfiles 17,097]

If you were to do a reverse gear reduction by changing the primary and basket gears you could achieve a higher top end ,  but it will cost you performance  across all gears and you will lose the low end umph  !!! 

 

If you want to go fast , then buy a Can-Am or a Polaris 

[Gravesdigger 2]

Fishfiles I had a Polaris Scrambler 400 many years ago and it was a lot of fun. When it ran. It would run 65 mph and go up hills, through mud, and over rocks just as well (and sometimes better) than any stock utility ATV. The problem was that it was a p.o.s that always had something breaking. I traded it for a '86 Kawasaki Tecate quad that I shouldn't have ever sold.

I just wish 5th gear would slow the rpms down. If you was able to put a lower (numerically) 5th gear in the foreman it would still have all that low end torque needed for a utility atv and be able to run with quads almost twice its size. My foreman can take off from a dead stop in 5th gear with 27 inch tires. 5th could stand to loose some teeth. 

[Fishfiles 17,097]

27 minutes ago, Gravesdigger said:

Fishfiles I had a Polaris Scrambler 400 many years ago and it was a lot of fun. When it ran. It would run 65 mph and go up hills, through mud, and over rocks just as well (and sometimes better) than any stock utility ATV. The problem was that it was a p.o.s that always had something breaking. I traded it for a '86 Kawasaki Tecate quad that I shouldn't have ever sold.

I just wish 5th gear would slow the rpms down. If you was able to put a lower (numerically) 5th gear in the foreman it would still have all that low end torque needed for a utility atv and be able to run with quads almost twice its size. My foreman can take off from a dead stop in 5th gear with 27 inch tires. 5th could stand to loose some teeth. 

'digger , I too had a Polaris , a 1999  500 Sportsman , it was fast like you mentioned , pegged the speedo , I'd say around 65 mph  , also was a P.O.S and always had something wrong with it , and always something expensive  , I traded it for this red 2002 TRX450 , done a lot of work to that one , it has 14.5% reduction  ------   also have a 2000 TRX450S , I don't think you would like this one , it has 34.5% reduction , top speed  in 5th gear with a strong wind at your back is 19mph