How do I get more LOW END power?

[gsmith]

Had the same issue with my 05 wr 250, after the free mods I installed hot cams and did a little jetting and used the moto billet endcap with really good results.

[peachvw]

Thanks everyone, Im gonna do some tests starting with the basic riding in third and lugging, then a new header (stock one is too tame) then some more mods...

Keep ya posted!

[Polar_Bus]

Thanks everyone, Im gonna do some tests starting with the basic riding in third and lugging, then a new header (stock one is too tame) then some more mods...

Keep ya posted!

If you have the stock WR exhaust cam, that's a real mellow torque cam. Simply adding the Yamaha YZF cam makes a huge difference in low to midrange acceleration. It's a solid performance boost for about $140

[gmoss357]

the cams are the same. the only reason to go to the YZF is to change the timing which affects how the power comes in, not actually adding any more. Still a worth while mod.

[ThumperMx365]

Any Pipe or Hot Cams.

[brutis1984]

I would not change the front sprocket to 12t that will drastically change the gearing. By changing the rear sprocket from stock 52t to 50t, 49t etc. will gain you a lot more tire rotation per rev at all rpms. Not more power but will put more of it on the ground. That will also make the tight trail come at you a bit faster with less engine brake but you will cover more ground at low throttle.

[gmoss357]

Brutis, I have often thought about going to a 50 tooth as high torque engines don't require as much gearing. I just didn't know how the bike would perform in the woods. I believe I would be in second most of the time where I am now in 3rd. Anyone with any experience on this?

[YZ250F_Rider]

Almost everyone rides with a 50T rear.

[gmoss357]

Almost everyone rides with a 50T rear.

I have a WR, it comes with 13/52

[YZ250F_Rider]

cough cough, almost everyone with a yzf, rides with a 50T.

[brutis1984]

I am currently running a 13/52 which fits the type of trail Ive been practicing on. But this past weekend I ran with some boys with 450's and they can gain 5ft or so in leaving turns, every turn. I was working extra hard to keep up. But when I ride with them again I will have a 50t on and that extra punch (tire rotation) out of turns will keep me with the pack. The really tight trail will need a gear lower than normal at first but after 20 or 30 miles it will come to you and feel right at home. You will have to raise your game a bit.

[gmoss357]

Do you have a WR or YZ. I tried a 53 tooth but it made 3rd wind out too quick and I feel like a 51 will put me in between gears. That is why I was wondering about a 50. I think for the most part Yamaha did there homework figuring out which gearing set up to use on the WR. I can't think of a better combo than the 13/52 stock. I am going to have to borrow a 50 from a friend though and do some experimenting.

[Doer]

#40 leak jet

Jd jetting kit

Powernow valve or make your own, see TT archieves for more info (Search "James now")

12 tooth counter shaft spocket

[aztsail]

I have a '04 250f with all the free mods done.

I would like to improve the low end power so I can chug along in a more relaxed style (Im usually following a mate on a 83 XR ? )

I read through all of the responses and I am surprised that no one mentioned buying a Dr. D pipe. I can tell you from my own experience, it makes a huge difference down low. Let me say that again, huge. One of the best things I did to my bike.

[Tysano]

buy a 450f

[brutis1984]

I'm running a WR. The 50 will suit your need very nicely.

I allready have a DR.D on and you are correct it has a nice kick down low. I am quite happy with the performance of the 250, it handles much better than the 450's IMO and with the right gearing the extra power is a non issue. Plus its much more of a challenge to run against the larger power plants; it forces me to get better.

[brutis1984]

#40 leak jet

Jd jetting kit

Powernow valve or make your own, see TT archieves for more info (Search "James now")

12 tooth counter shaft spocket

I don't see how a leak jet will create more low end power. The leak jet just controls the amount of fuel allowed to reside in the accelerator pump it doesn't provide more fuel to the motor, it does help eliminate the bog but thats not the problem. Also the 12t sprocket will require the motor to turn more rpm's to get the same rotational output as the 13t (you'll be revving higher but not going as fast). My attempt in bringing up sprockets is to help him get more existing power to the ground with less rpm's (low end) and less cost.

[gmoss357]

brutis, what gear do you run in the woods mostly, 2nd or 3rd? I take it y'all have some tight woods and knarly hills out there? I just worry I won't be able to stay in 3rd and pull small rutted switchback hills or slow bermed corners where I usually clutch and roll out in 3rd gear. If I can borrow a 50 tooth from a friend I am going to test it out.

[brutis1984]

gmoss, It all depends on the terrain at a particular course. I will run 1st, 2nd and 3rd at all wooded trails. A 30 to 40 degree downhill with bowling ball rocks I'm in first trying to stay upright and not slide. If it has small or no rock I'm in 2nd or 3rd accelerating. Some real tight stuff requires 1st regardless. All courses will take all gears to maneuver efficiently. You will adapt quickly to what ever gearing you run. You will still have all your gears and one of them will be right for the situation. Dropping to a 50t will not change your riding style very much. You are used to grabbing third out of turns, the 50 could allow you to continue to accelerate out in 2nd and grab 3rd in a straight, or stay in 2nd through the next turn. It could help you to not have to shift as much and be able to use throttle control, which is much more efficient than gear changing.

[gmoss357]

I finally got to try a 50 tooth on someone else's bike yesterday. Only difference is that they have a Dr D pipe where I have a YZF pipe. I like my 52. With it, I can stay in 3rd more and use 2nd for the steep climbs and quick stop and go's. The only time I need 1st for the HS's is for the start and, like you said, really steep decents, other than that, I can take off in 2nd or 3rd from just about a stop. 2nd gear was still too jerky for throttling out of corners, wanting to launch the bike into the woods. Our series has some very tight single track but I never need 1st. The more you can use 2nd - 3rd, the less you are miss shifting into neutral. I believe Yamaha has done their homework and put the proper gearing on the bike from the get go. But of course, that is just me.