Jumping and Throttle Position (4 Stroke)

[MJ27]

I grew up riding 2 strokes, then got out of the sport for 10 years. I finally got back into it by buying a 250F and I'm having some trouble jumping.

I endo off of almost every jump. I find myself backing off slightly on the face of the jump, then blipping the throttle during takeoff. I try to leave the throttle open until my back wheel leaves the ramp. Is this the correct way to jump a 4 stroke or should I be keeping the throttle constant from the start of the face to takeoff?

Thanks for the advice!

 

[bluerider125]

yes.

 

[James]

Haven't ridden a YZF yet but I had just the opposite experience when going from an XR400 to a CR250..was always looping out and getting thrown off of the back of the CR.

I found that accelerating over most jumps was the best on the XR. Usually hit the gas hard in 2nd or 3rd on the approach to a ramp and accelerate through the jump. Blipping works too - but requires a bit more skill with the timing and throttle control. From what I understand, the YZF is comparable to a modded XR400 in the power dept...am I wrong? Holding the throttle constant would usually get me front end low. I guess you could do constant throttle on a downhill jump.

 

[High Lord Gomer]

Some 4 strokes don't respond well to bliping the throttle on the face of a jump. The 250F does, so that shouldn't be a problem, but I still maintain steady throttle all the way up a jump when on a 4 stroke.

That has bitten me when riding the too-powerful 426s, though (sorry, ByrdMan).

Letting off in the air will drop the front of a 4 stroke more than a 2 stroke, too. That may be part of the problem.

 

[los36]

I ride an RM 250. Very responsive engine. There was this one double at a track in Floresville, TX that I would accelerate up to, scub off some speed and blip the gas as I was leaving the face. I was clearing it perfectly every time.
I got on my buddy's CRF450 and nosed into it every time until I adjusted my style. The throttle response is nowhere near my RM. Instead of blipping the throttle as I left the face, I had to scrub off less speed and roll it on all the way up the jump.
Also, since blipping is usually a quick twist of the wrist, you may be rolling off the throttle before the back tire has left the ground...resulting in the endo feeling. I've never ridden a YZ250F, but suspect that you may want to get out of the blipping habit and concentrate on carrying an amount of speed that will allow you to apply at least some throttle all the way up the face.

 

[jmics19067]

when I had my wr400 it would seriously nose dive if I shut off the throttle.
if I came to the jump too fast and tried to quickly slow down and get back on the throttle to keep from nosediving<blipping> I hard a very harsh uncomfortable take off that would just about throw me off . The bike woudl have a nuetral flight to it but my feet would always end up around the seat .
when I hit the jump with a steady increase in throttle it was just sweet picture perfect beuatiful thing.
this same jump on a yz250 2stroke is a lot more forgiving when the throttle is not being opened but a lot more likely to loop out when hard on the throttle

 

[rockchucker]

MJ27, do not blip the throttle on the YZF. That causes the opposite effect that you think it should have... as you've found out. Hold the throttle on constantly up the face. Roll on the throttle smoothly and keep it on until your REAR tire leaves the ground. Of course this scenario is dependent on type of jump, riding style, etc... But for the most part keep the weight centered and the gas on. Also improper suspension set up can cause this effect but maybe not to the degree you're experiencing. You definitely have to plan your jumps a little more than you would on a two stroke but once you get it down the nose-down attitude of the 4 stroke can work in your favor... i.e. more acceleration on landing.

 

[James]

Gomer, when you say "constant throttle" do you mean get the throttle in a position and hold it over the jump OR do you mean a "constant speed" as you go up the ramp (which would mean you have to give it a little more upon hitting the ramp).

Seems to me, if you hold the throttle in one position you actually decelerate upon hitting the ramp and that gets my front end too low on the 4 stroke. But if I maintain "constant speed" or accelerate slightly (as I prefer), the bike will fly level.

Not trying to split hairs but just want to clarify as I am getting a little confused myself (not out of the ordinary). I'm not an expert by any means - you can vouch for that.

 

[High Lord Gomer]

For me, constant throttle means a constant throttle position that is accelerating. I use the term to distinguish from blipping the throttle on the face of the jump. I also use the term when trying to keep people from revving and releasing on the starting line.

When I started jumping I would always grab one more gear before a jump and hit them at near full throttle, but with low RPMs and therefore not much power. It was more consistent for me than trying to find the proper power setting while at higher RPMs.

You're already beyond that point and should practice hitting the same jump with more speed and less power as well as with less speed and more power (obviously varying your body position to adjust for the difference in acceleration). There are times when both approaches are useful.

 

[James]

Gotcha!

 

[MJ27]

Just to follow up...I went out to the track again and found that basically what rockchucker recommended worked best. I'm also a little bit short and I think I was keeping my weight too far forward (short arms). Now I keep constant throttle or accelerate on the face and I clear most obstacles just fine.

Thanks to everyone for the advice!

 

[Thump]

I am the opposite from most... I blip the throttle on almost every jump. The amount I blip depends on the take off face..... Works for me.

 

[crkid]

I guess whatever works, but if I did that on my buddy's 426, I would die.

 

[Okiewan]

Works for me.

That will cause most people to jump front end high :confused:

Constant throttle, head over the bars, chop it on take-off... "blipping" takes timing that may not always work (ie; 4 stroke bog, bad timing)... jump flat, it's a lot eaiser to get the front end up than it is to get it down.

 

[MrLuckey]

Boy isn't that the truth Okie. This past weekend I kept changing from a TTR250, KTM200 and a WZ426 (Death From Above) and found the front end way up and way down a couple of times due to the differences. I thought that 2 stroke was going to kill me a couple of times, felt like pure vertical (front end high) after nose diving the 426 a couple times :)