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Discussion Starter · #1 ·
I have an 07 Honda rancher 400 at. I put 26” ams slingshot tires on and want my power back. Has anyone put a clutch kit in this and how did it work. Thank you
 

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I have an 07 Honda rancher 400 at. I put 26” ams slingshot tires on and want my power back. Has anyone put a clutch kit in this and how did it work. Thank you
Welcome to the forum.

There are a few remaining 400AT regulars left here. But I don't know off hand any that are running a clutch kit. But by a clutch kit you basically mean stall springs, right?

You can certainly install them and they will certainly raise your engagement rpm, but I personally would recommend against doing so.

Basically with installing 26" tires you raised your final gear ratio by 8.3%, and you added rotational mass. The only way to get that back is to lower the gear ratio elsewhere. That is why you see others with other bikes installing GR's (which aren't available for the 400AT's).

Raising engagement rpm doesn't increase the actual output of the motor. So if it were me, I would run a 400AT with 26's in ESP mode and keep the engine rpm up that way, with a stock clutch.

Because the other downside to stall springs is they actually REDUCE the engagement force in the centrifugal clutch. Which causes excess heat and slipping in a clutch that is already on the weak side, with tires that are now adding excess load.

And to compound it further, the ECM on the 400AT doesn't appropriately handle a slipping clutch in Auto mode.

I know that isn't the answer you wanted to hear. Probably the best way to get a better understanding of it is to read up on wet clutch slugs for the Yamaha Grizzlies. They do the exact opposite of the stall springs. But when you combine that with a shim in the cvt to lower the gear ratio, magical things happened. Pretty much nobody on grizzlycentral.com uses stall springs anymore because of all the problems they created.
 
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Discussion Starter · #3 ·
Thanks for the info. Do u really think that if I go down a size to 25s that I would be helping or should I stay with my 26s? And can I put a jet kit in and good air filter without a pipe and gain or not?
 

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Thanks for the info. Do u really think that if I go down a size to 25s that I would be helping or should I stay with my 26s? And can I put a jet kit in and good air filter without a pipe and gain or not?
25's should get you back half of the final gear ratio change you lost. So not significant, no.

A jet kit will only get you more power if you can increase your overall flow through the motor, by improving the limiting factors. You still need to keep your air/fuel ratios rights. And it’s not like these are DOHC 4-valve motors that are limited by little things in the intake or exhaust that can be improved. The 400AT is a push-rod, 2-valve motor that is limited by that being its configuration, and not the intake or exhaust. If you look at your stock air filter dual layer foam design, it is very similar to much higher HP mx bikes. So that is obviously not a limiting factor. You can make those changes you mentioned and it certainly won’t hurt, but will cost big $$. In other words “the juice isn’t worth the squeeze” in this case.

If you really want more hp and capability, this is a case of “there is no replacement for displacement”. Oh, and that hydrostatic tranny robs a lot of hp too.
 

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I’m amazed you can tell the power loss running 26’s, how heavy are they? Also, the clutch shouldn’t slip at all running that size tyre, if it is it’s shot and wants replacing anyway. Stick with OEM springs or an equivalent, HD won’t be beneficial for you whatsoever.

An alternative would be to run skinny lightweight tyres all round with no reduction or get a reduction made, 15% would do it perfectly.
 

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I’m amazed you can tell the power loss running 26’s, how heavy are they? Also, the clutch shouldn’t slip at all running that size tyre, if it is it’s shot and wants replacing anyway. Stick with OEM springs or an equivalent, HD won’t be beneficial for you whatsoever.

An alternative would be to run skinny lightweight tyres all round with no reduction or get a reduction made, 15% would do it perfectly.
Have you ever ridden a 400AT, Sam? They may have more cc than a 350 Rancher, but the hydrostatic inefficiencies and lack of a dedicated Low range make them feel like they have less hp. And nobody has ever made a GR for one as far as I can see.
 

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I’m amazed you can tell the power loss running 26’s, how heavy are they? Also, the clutch shouldn’t slip at all running that size tyre, if it is it’s shot and wants replacing anyway. Stick with OEM springs or an equivalent, HD won’t be beneficial for you whatsoever.

An alternative would be to run skinny lightweight tyres all round with no reduction or get a reduction made, 15% would do it perfectly.
Have you ever ridden a 400AT, Sam? They may have more cc than a 350 Rancher, but the hydrostatic inefficiencies and lack of a dedicated Low range make them feel like they have less hp. And nobody has ever made a GR for one as far as I can see.
Ahh ok, I have ridden a 400 but It was years ago, to be totally honest I can’t remeber if it was auto or foot shift. Auto’s do sap power though, your spot on
 

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I’m amazed you can tell the power loss running 26’s, how heavy are they? Also, the clutch shouldn’t slip at all running that size tyre, if it is it’s shot and wants replacing anyway. Stick with OEM springs or an equivalent, HD won’t be beneficial for you whatsoever.

An alternative would be to run skinny lightweight tyres all round with no reduction or get a reduction made, 15% would do it perfectly.
Have you ever ridden a 400AT, Sam? They may have more cc than a 350 Rancher, but the hydrostatic inefficiencies and lack of a dedicated Low range make them feel like they have less hp. And nobody has ever made a GR for one as far as I can see.
Ahh ok, I have ridden a 400 but It was years ago, to be totally honest I can’t remeber if it was auto or foot shift. Auto’s do sap power though, your spot on
I don't think actually turning the 26's is the problem at hand or what the OP is asking about. More about just trying to get the original power feel back into it.
 

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Discussion Starter · #9 ·
You guys are definitely helping with your knowledge. I think I’ll just leave everything the way it is and go lower on the tires to ams swamp fox 25s instead of these aggressive 26s
 

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You guys are definitely helping with your knowledge. I think I’ll just leave everything the way it is and go lower on the tires to ams swamp fox 25s instead of these aggressive 26s
Still sorry though. I wish for your sake of having fun somebody made a GR for the 400AT. Heck I'd like to have it and then be able to run 25's or 26's while not stressing my clutch any more. A GR could be done to anything, but nobody took the time to make one available for the 400AT.
 

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So I shouldn’t be running my 26” ams slingshots?
Only you can say whether your 400AT can handle the 26's or not for your riding. And if you don't mine putting a clutch weight set in a little more often, then very much go for it. It's just in my experience and others that the 400AT's are more affected by going oversize than other Honda utility models. Just trying to be honest about expectations.
 

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Discussion Starter · #13 ·
Yes u are helping me out a lot. I just don’t wanna year anything up. And so far I haven’t but I’m considering going back down on tire size but I have 12 inch rims and don’t wanna get different one. I would like to find tires that are 24-8-12 for front and 24-10-12 for back if possible
 

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Yes u are helping me out a lot. I just don’t wanna year anything up. And so far I haven’t but I’m considering going back down on tire size but I have 12 inch rims and don’t wanna get different one. I would like to find tires that are 24-8-12 for front and 24-10-12 for back if possible
I thought based on the title of your other thread you are looking for 25's? And then here you are sounding like you want to run your 26's.
 

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Discussion Starter · #15 ·
25s would be better on clutch right? Then 24s even better? I didn’t do my homework when I bought 26s. I may just run the 26s till I burn the clutch up lol
 

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25s would be better on clutch right? Then 24s even better? I didn’t do my homework when I bought 26s. I may just run the 26s till I burn the clutch up lol
Absolutely, look at my signature, that is why I run 23s. Though I know that is extra conservative, just trying to make mine last as long as reasonably possible.
 
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