Xr 400 16 tooth front sprocket fit

Looking to get a little more speed out my xr400. What's the best way to get to fit with the chain / case guard? Should I grind or modify it, or maybe an aftermarket guard?

Curiously what are you currently running gearing wise because if you were running say 15/40 i highly doubt the 400 would be able to pull it to top speed anyway?

Looking to get a little more speed out my xr400. What's the best way to get to fit with the chain / case guard? Should I grind or modify it, or maybe an aftermarket guard?

With the 16 tooth and stock "case saver" you will have to grind it until the chain fits. It was just a thin piece of metal after I got done doing mine. I am running the XR's only case saver and chain guard. You have to grind on the chain guard some. If you just run the case saver you have to put some washers between the case and the case saver to space it out so it runs in the middle of the chain.

Looking to get a little more speed out my xr400. What's the best way to get to fit with the chain / case guard? Should I grind or modify it, or maybe an aftermarket guard?

I install my 16 like any other size sprocket. No mods required. Edited by YHGEORGE

Curiously what are you currently running gearing wise because if you were running say 15/40 i highly doubt the 400 would be able to pull it to top speed anyway?

Right now I'm running 15 / 45. I guess I should have explained better, but top speed isn't what I'm looking for. Just a little lower rpm near the 60 mph range. Now when I'm on the road I always find myself trying to shift one more time.

Drill out the mount holes larger on the case saver and cover to get a little more clearance as well. That and a little grinding will get everything back on with a 16T front. Switching to a 16 front will get you about 4-5 mph more in 5th gear at the same RPM.

Good advice.

Drill out the mount holes larger on the case saver and cover to get a little more clearance as well. That and a little grinding will get everything back on with a 16T front. Switching to a 16 front will get you about 4-5 mph more in 5th gear at the same RPM.

Dennis Kirk sells a sunstar 39 tooth rear sprocket for the xr4 as well, I ran a long road tour last fall with the 16x39 combo and just received a new set for this coming season.

I don't have a tach on mine but 60 is a real comfortable run with those gears. I haven't had any issues with my bike pulling the top gear, I tend to run secondary roads at around 60 but my route took me over a lot of passes and if you put the wood to it and wind it up a bit you can pull 70 and 80 and it's a lot of fun.

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I run 16/45 to work at near highway speeds it gets alittle revy but much better then the 15. Needed no mods to case either.

you can run the counter sprocket cover with a 16T on the front. just use 7-8 washers with the top bolt and 4 washers on the bottom bolt to give you clearance. make sure one of those washers is a lock washer. this works perfect and keeps your feet away from the sprocket. I just changed mine today from a 14t to the 16t. I Don't use the case saver with the 16T just the sprocket cover and it works fine, been doing it for two years with no problems!

Also with the 16T on the front and the stock 45T on the back your xr4 should top out in the mid 80's. Mine hit 86mph. But runs at okay rpm's at 55-60mph!

Edited by XL100allnightlong

I've done the exact same thing as XL100 above. Was happy with the new gear ratio, but still looking for a bit lower RPMs at highway speed. Bought a 42T rear over the winter, hope that satisfies for at least this year. I'll install that this week.

Didn't know that a 39T was available, or I may have gone that route. Maybe next year.

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