[Matt7635]

Hi there!

For the people who have changed the gearing on their 400s, do you regret it, or advocate/would do again? I want a bit more acceleration, so I'd want to go either 4 teeth up in the back or 1 less in the front. I know a tad bit about suspension for cars/bikes, but I never dabbled in the powertrain aspect much. Is going -1 F or +4 R essentially the same? And would any of those changes cause the CEL to popup? Thanks in advance fellow four hundo riders!

 

[Banjoboy]

Can't speak to gearing lower, I went up 1 tooth on the front. Since I got the full Akra, K&N, 'n ECU flash, it seemed like I was always shifting, and taller gearing would give me more "pull" through the gears. I've only dun a few short rides, so the juries still out, butt it seems better.
When you change yer gearing, yer CEL will come on, 'n yer gear position sensor will go bonkers. READ THIS to cure that.

 

[rkturbo]

Let’s start with the simple answers. If you want greater acceleration (as the cost of top end speed), going down teeth in the front/up teeth in the rear will accomplish that. The reason being each rotation of the front sprocket moves 1 less link or chain per rotation; similarly to how more teeth on the rear make the chain move the rear wheel assembly the respective number of teeth less. The opposite is true, bigger front moves more chain, smaller rear requires less chain movement to make a full rotation. I will say that any change to the front sprocket, and a change greater than +/-2 on the rear will trigger the CEL. Fortunately that’s an easy fix by using a jumper wire across the clutch switch. There’s a thread or two around here about that. A change of +/-1 in the front is incredibly popular. I preferred going up in the front to lower my RPM at highway speeds. A lot of those going to the track like a -1 in the front because of the increased acceleration, and feeling of more power/torque. I don’t have a solid opinion on which way people should take gearing, items very personal to what you want to accomplish in the end.

 

[Kiwi Rider]

Dont forget about chain length and axle position in the swing arm slot. I can tell you for a fact that you will need a new (longer) chain if you add four teeth to the rear sprocket as the axle will hit the front of the swing arm slot. Better to drop 1 tooth on the front sprocket which wont change your axle postion or your geometry too much. Encase you dont already know: the rough rule of thumb is one tooth on the front is equal to three on the rear.

 

[Tracy]

I went -1 on the front. Didnt like it, way too much for my liking. Don't care about top end, rode 90 mi. today after work used 6th gear 4 times. It depends on your riding style. I put 14t back on front and went up on back only 1t to a 42t. For where and how i ride it works for me but maybe no one else. You will have to buy a couple of different sprockets and play with it to find your "zone" And like Kiwi said you have to plan your chain length accordingly.
🐉

 

[Surge]

Went - 1 in the front and +2 in the rear. It definitely accelerates faster, but it's ridiculous on the freeway. In 6th gear at 85 mph I'm at 8,500-9,000 rpm's. It works good for the canyon, but not much else. I used a longer chain to get it to work.

 

[4040]

I added 2 to the rear sprocket with a light aluminum sprocket and low-friction, gold chain. Result: Smoother drive. Better acceleration. Slightly less top end. No CEL. Looks better IMO.

 

[JFMNINJA400]

I went +1 in the rear with a sexy blue Driven aluminum sprocket. No CEL, and I love the extra kick! I do mostly track on the 400 so I want as much top speed as possible but some extra grunt coming out of the corners. +2 rear sprocket will not fit with the stock chain. If you do -1 front and +2 rear that should fit with the stock chain, it may trigger the CEL.

 

[Matt7635]

Hm I may end up going the -1 tooth in the front route to avoid the chain issue. Checked the link and wow that little u shaped wire thing is all it takes?? I was also told by a local mechanic that I should replace everything as a kit, both sprockets & the chain. The sprockets look like they are in good shape and the chain as well (about 8k miles on the bike, the first 6 was from the first owner drove extremely conservatively). I guess it's time to do some research if they sell front sprockets by themselves & how hard it is to install it yourself (not extremely mechanically inclined, but I have done some fun jobs on the bike/car).


Thanks everyone for your input! Also, if anyone is in the LA area, would love to go on a ride sometime!

 

[Tracy]

Edit....my bad...misunderstood

 

[Banjoboy]

Hm I may end up going the -1 tooth in the front route to avoid the chain issue. Checked the link and wow that little u shaped wire thing is all it takes?? I was also told by a local mechanic that I should replace everything as a kit, both sprockets & the chain. The sprockets look like they are in good shape and the chain as well (about 8k miles on the bike, the first 6 was from the first owner drove extremely conservatively). I guess it's time to do some research if they sell front sprockets by themselves & how hard it is to install it yourself (not extremely mechanically inclined, but I have done some fun jobs on the bike/car).


Thanks everyone for your input! Also, if anyone is in the LA area, would love to go on a ride sometime!

Yes, the u shaped wire is all you need, but once you do that, you'll no longer have the safety switch; mean'in if it's in gear, 'n THE CLUTCH IS OUT, the bike can start 'n send you flying!
If I'm replacing an old chain, I'll do the sprockets too, but when experimenting with gearing, I wouldn't worry 'bout it.

 

[Matt7635]

Yes, the u shaped wire is all you need, but once you do that, you'll no longer have the safety switch; mean'in if it's in gear, 'n THE CLUTCH IS OUT, the bike can start 'n send you flying!
If I'm replacing an old chain, I'll do the sprockets too, but when experimenting with gearing, I wouldn't worry 'bout it.

Noted, and thank you sir!

Regarding the safety switch, that isn't an issue. I almost always do a clutch override on my manual autos. This will be on my list to do if I keep the bike for another like 6 months... I don't want to throw hundreds of dollars experimenting with sprockets at the moment

 

[airhead83]

To Banjoboy's point. An auto, with 4 wheels may not cause a big problem if the clutch and starter are engaged incorrectly.. A motorcycle will dump you on your arse.. and embarrass you in a hurry. Just saying.. But, I'm old, slow, and forgetful, so I need all the built-in safety devices my bike offers. Maybe not a big deal for you, though. Just a reminder.

 

[Matt7635]

Good to keep in mind! Not sure if other's have had this issue, but I've noticed sometimes when I kick the bike into neutral to start, it drops back into first. This happened twice. But I'm typically on the bike when starting and holding the clutch/brake. Although... Murphy's law >.>

 

[ChazakAmatz]

+2 in the rear making it 43 is exactly what I'm ordering today... just to get an idea what kind of torqur does it give? Can you get the front end up in 2nd? And how many links? 107 or 108 🏍

 

[Duckman]

+2 in the rear making it 43 is exactly what I'm ordering today... just to get an idea what kind of torqur does it give? Can you get the front end up in 2nd? And how many links? 107 or 108 🏍

108 with a 43 or 44. I run 43 most of the time. Usually on starts when I shift to second it carries the front about 3-4” off the ground for a couple seconds.

 

[ChazakAmatz]

Noice! Thanks. Sounds like its gonna fun! I'll stick to +2 rear so I won't throw a code. Stick to steel sprocket since ill be riveting the new gold chain on and ill have the torque I wished for. Thanks!

 

[Tracy]

See what you done went and did Duckman!!
🐉

 

[ChazakAmatz]

43 tooth Vortex and Rk 108 Gold chain order. Woot woot! Now maybe I can kick it back like the Dr-Z beside me this mornin did 🏍

 

[ChazakAmatz]

Update. Life sucks lol. I made a bad move. A few site were sold out of the vortex sprocket I wanted so I went to Amazon and ordered a 43 tooth Vortex with six bolt pattern... only to find out after cutting off the chain thinking all was good it wasn't. It doesn't fit smh. I guess me being new this is what I get. How do you guys know for sure its going to fit?