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There's a problem in your logic ballistic. You assume that just because someone is pushing the front, that they have reached maximum velocity for the turn. NO WAY! I teach at a lot of trackdays, and I see people sliding things all over the place going SLOW! They just suck, or they are trying to hard and are too tense on the bars, etc. Anyway sliding is far from indicating that you have reached maximum speed.

 

Also, if you are letting go of the brakes late enough to keep the front end from rising, then you ARE trail braking, no question. You likely can release the brake before reaching max lean and therefore sliding the front is irrelevant because you off the brakes by then anyway.

 

OK Dude ease up for a minuet. I say these things based on my riding and observations I make are of what I think is the limit of turn speed which may be justified as correct by my race results in WSMC and CCS. For the sake of discussion I am not taking into account riding errors, but now that you mention it the errors you stated would get you to the ground faster with trail braking than without it.

Now to the real deal. What is trail braking ... Is it letting off the brakes slowly or letting off slowly after you start turning... If it either one of those don...t do now and never have. I turn the bike very quickly. And at the moment I release the brakes. So all my braking is done before I start to turn.

There are always turns were you must brake wile leaned over but my style remains the same I get the braking done and then turn. Make no mistake I can use the brakes at full lean and had to this last weekend, I instantly bottomed the forks and started the front hopping and clanking, Then I realized the only way out was to run off and l let go of the brakes and stood it up off into the dirt missing the leader by inches. Oh he was trail braking and stood a lapper up into me so I was way deeper than normal, when I got around him I found the leader still hadn...t turned and I almost T-boned him.

I will use any tool I think is effective to lower my lap times but this one as I understand it isn...t one of them, I have heard many times that I leave the inside open and will be passed by the ...fast guys.... I hear them come up but by the time I turn silence, I am on the gas and they are still trying to slow down.

Will Eikenberry WSMC # 363 CCS # 63

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I wasn't trying to start a pissing match, but when you said most people can go fast enough to slide the front, I took exception. I wouldn't pretend to know your skill level.

 

Now that you mention them, you're credentials make you faster than me. I'm .8 seconds off the 125 record at Loudon if it matters, but here's a question:

 

If you're method is THE fast one, then why do ALL the motoGP racers trail it in deep?

 

I understand they have more HP, but couldn't they go even faster if they didn't do it?

 

I mentioned earlier that I made big gains lat in the season by staying on the gas DEEP into the turns. I had stopped getting faster getting off the brakes before turn-in.

 

Now, I trail brake in most turns. It may be a difference in bikes, rider styles, traction levels, etc. I honestly don't believe one way is better than the other. I'll use whatever gets me the results. Right now, that's trail braking. If I stop getting faster with this approach, then I'll consider trying to get new results with other techniques.

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If you're method is THE fast one, then why do ALL the motoGP racers trail it in deep?

I'm sorry but this is a complete BS statement. How do you know that all the moto gp guys trail brake? Even if they all do trail brake I would bet any amount of money that they do not do it in every corner.

 

I don't think Will is saying that the way he rides is the only way or that it is THE fastest way around a race track. It is the way he rides and he is not conviced that he could go faster using trail braking.

 

Back to the subject at hand.

 

Do you trail brake in every corner? or just certin types?

 

 

I do not trail brake in every corner. Let's take Laguna Seca for example... I would never even consider trail braking into turn 11 at Laguna unless I was trying to pass someone (and chances are,as we have seen several times, they would have a good shot squaring me off if I did) but I was trail braking pretty much every lap in turn two.

 

Balistic- Do you trail brake in turn two at Laguna? This seems like a great corner for using this tech.

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I wasn't trying to start a pissing match, but when you said most people can go fast enough to slide the front, I took exception. I wouldn't pretend to know your skill level.

 

Now that you mention them, you're credentials make you faster than me. I'm .8 seconds off the 125 record at Loudon if it matters, but here's a question:

 

If you're method is THE fast one, then why do ALL the motoGP racers trail it in deep?

 

I understand they have more HP, but couldn't they go even faster if they didn't do it?

 

I mentioned earlier that I made big gains lat in the season by staying on the gas DEEP into the turns. I had stopped getting faster getting off the brakes before turn-in.

 

Now, I trail brake in most turns. It may be a difference in bikes, rider styles, traction levels, etc. I honestly don't believe one way is better than the other. I'll use whatever gets me the results. Right now, that's trail braking. If I stop getting faster with this approach, then I'll consider trying to get new results with other techniques.

I didn't say anything about what others could or couldn't do just what I do and don't. I posed a couple of questions about turn entry that haven't been answered though.

I don't now nor did I doubt your ability or anyone else's. I don't base what I think works or doesn't on a persons ability but it is nice when you can get someone to try something and then be able to honestly evaluate how it worked.

I never said "my method is THE fast one". I do not pretend to the man only one who can ride with some degree of proficiency.

You think all the GP guys ride the same, I don't. Rossi, McCoy, Bayliss, Biaggi. These four guys ride totally different. I don't believe they all subscribe to any one technique and do it the same.

I would ask you the original question once more, is it possible to go fast enough into a turn to slide the front? If you can answer that with yes then the only conclusion you can come to is if you have traction left to brake your going too slow.

Will

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Well turn two is an anomaly for sure. just riding around I like the turn point we put out but I have played with others and I wouldn't run outside like that in competition. I like to low line it and try not to leave enough room on the inside to be passed. it blows the drive but your either open to be passed going in or coming out.

The answer to your question is no I don't as I understand it trail brake there. I have however used the brake once turned to adjust my line.

I have blown turn entry ( turn two at streets) so bad I knew I wasn't going to make it. Im on the brakes coming to my turn point and I can tell im going 5 to 7 mph to fast ( I turned the idle up from 1,000 to 3,000 and it just didn't stop quite the same) I release the brake, turn, back on the brake until a couple feet from the dirt, release the brake, turn and off into the dirt I go. I have a mental block to turning with the brake on even in an emergency.

Will

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OK, Sorry about the generalization, but when I watch those guys back it in so often, it's pretty clear to me that they trail brake. But they may not do it all the time.

 

To answer your question then, Yes on occasion I have pushed/drifted the front, both on and off the brakes.

 

It seems to me that the front doesn't usually push til mid-corner. That still leaves some time for trail braking. I'm not set on this. There are corners where I don't use the technique. Why? that's what I'm trying to figure out. Your input is appreciated.

 

btw, congrats on the lap record! That ROCKS!

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but when I watch those guys back it in so often, it's pretty clear to me that they trail brake.

Most guys use the clutch-engine braking to back the bike in, not the brake, this is a different technique from trail braking. Plus most of the slideways stuff is happening before they put the majior steering input into the bars, isn't it?

 

Seems like decreasing radius corners are good canidates for trail braking and increasing radius corners are not. Sound about right as a general rule?

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Yeah - Yates gave a great interview to Speed last summer regarding this subject. He said he tries to prevent sliding the back before corners by managing the clutch, but at Yates' level it must be really difficult keeping the back end in line.

 

Seems like decreasing radius corners are good canidates for trail braking and increasing radius corners are not. Sound about right as a general rule?

 

I can think of a couple good candidates for trailing the brakes, but the corner I do it most often is a decreasing radius turn out here in California (Button Willow). I doubt Will trails there either, but it seems to work for me (especially when someone tries to low line up the inside of me).

 

This string really got me to thinking about [trail] braking, so this past week at Laguna I really thought about my braking and came away with some really good observations. I did try trailing more here and there, and generally, I felt more comfortable finishing my braking before the steering input. Another observation I have is it is very important for me to release the brakes smoothly. Qucikly for sure, but smoothly. I never just release the brakes by letting the lever "pop" out of my hand.

 

As Keith and Will point out though, the time between releasing the brakes completely and turning the bike is so short that I think I usually error one way or the other (release the brakes too soon or too late). Since I have been really thinking of this, I have already noticed improvements. Maybe we can convince Keith to develop a level IV braking drill for us :)

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I love this thread already, but we still don't have a definition of trail braking?

 

What is it? is it letting off slowly as you turn or using the brakes wile leaned over? Is it just the front? does backing it in count?

Will

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I have been operating under the premise that trail braking means coming off the brakes after the initial steering input. There are a couple of internet sites which offer definitions (see link to Sportrider below - not that they are an authority or anything, but I figure we need to pick a definition and go with it).

 

So, I figure that if you begin your steering input before you are completely off the brakes, then you are trail braking to some degree. This definition would include coming off the brakes while making the steering input or come off the brakes after steering is complete. Comments? Agree, disagree?

 

http://www.sportrider.com/ride/146_9508_rss/

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I was going on the definition Steve mentions, letting off the brakes after steering input. Of course it includes braking at any angle of lean. Keith mentioned earlier, it is likely to occur to some degree in every turn.

 

You guys have an advantage over me. It's snowing like crazy here and my bike is in pieces. :(

 

OT- As for backing it in, sure I understand that engine braking is coming into play, but there are 2 different things I see out there. The b. bostrom style wagging the tail under heavy engine braking/rear brake. This clearly can occur with out trail braking. Then there is the Rossi style where the bike doesn't wag, but steps out in one direction. I assume this can only happen with the front brakes applied and some steering input. In fact, he has countersteered by default in this situation.

 

When I rode diesels I found this happening in the pre-turn for T1 at loudon. Heavy front brake and a slight preturn was all that was needed to back it in (engine braking at normal/non-skid levels). As soon as I let of the brake the rear hooked up and I laid it over.

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Paab - Sorry to hear about the weather. It got down into the 60's at Laguna last week. It was almost unbearable! j/k :)

 

I try not to slide my bike on the approach to turns and rarely do, but I find if I go down too many gears too soon, I too get my back-end dancing around (like backing it in 4 or 5 times for one corner - how embarrassing). I have found though, that if the back end starts to dance around just a hint of rear brake helps to settle the bike (although I do not understand the science behind this, it seems to work). This is a very delicate matter though, as just a touch of rear brake is usually enough to get the back end to step out.

 

I think you are right about the steering input too. When you are hard on the brakes, you will no doubt have some input through the bars however little. So, it stands to reason that the combination of loading the front under heavy braking and going down a bunch of gears can result in the rear end sliding. I think the key here is not to down shift too soon.

 

I am not to keen on the concept of engine braking though. I think if you are riding fast, and braking hard, you probably are not getting that much benefit from engine brake (especially those of us on 125's and 250's), becasue in the brake zone you are so hard on the brakes your rear tire has very little weight (if any) on it and therefore very little stopping power. Maybe the big twins are different, but I really only on front brakes to slow me down (unless I am riding significantly off the pace).

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I have been operating under the premise that trail braking means coming off the brakes after the initial steering input. There are a couple of internet sites which offer definitions (see link to Sportrider below - not that they are an authority or anything, but I figure we need to pick a definition and go with it).

 

So, I figure that if you begin your steering input before you are completely off the brakes, then you are trail braking to some degree. This definition would include coming off the brakes while making the steering input or come off the brakes after steering is complete. Comments? Agree, disagree?

 

http://www.sportrider.com/ride/146_9508_rss/

that is what I think it means too.

Will

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What I love about forums is their thought provoking aspect. Rider?s comments, and personal experiences make me think. Behind every answer is a question and behind every question there is an answer. This trail-braking issue brings up a load of both.

 

Ever since I first investigated trail-braking and graphed it and set up some guidelines for it in the first ?A Twist of the Wrist? book in 1981 I?ve mainly focused on its more basic aspect, that of a rider?s Sense of Speed.

 

Sense of Speed is a rider?s ability to accurately judge differences and similarities in speed from one pass through a corner to the next time they encounter it. No matter how or when a rider is braking his Sense of Speed directs the whole activity. This is the irreducible part of the rider/bike/road combination which must be in good working order.

 

Following right on the heels of this sense is the rider?s Sense of Traction and I?ll talk about that a little later in this.

 

One of the other main issues that revolve around braking is the suspension action. The compression and extension that can occur with either 1) straight up braking or 2) trailing brakes into the corner.

 

Cornering enthusiasts both feel it and understand that making the transition from on to off the brake(s) and entering the turn should be as seamless as possible in order not to upset the suspension (read traction).

 

On a telemetry graph it would look like a continuous line as the rider released the brake and the cornering forces took over--that goes for either method of braking.

 

Now if you look at this aspect closely you will see that there is actually another sense which we develop to comply with this demand to make that transition a smooth one.

 

In order to make this work out we first of all must be aware of the bike?s dive attitude (how far down is the nose of the bike). In order now to make it successful the rider must also be aware of the compression the cornering forces will provide for the speed he has entered the corner. How much will it compress from that force?

 

A straight line braker?s ability to reckon where the suspension compression will be once he is into the turn plus his timing of letting off the brakes and turning to maintain the compression at that level have to be very good.

 

The trail-braking rider feels his way into the turn more on his sense of traction and has both forces (braking compression on the suspension as well as the cornering forces on it) acting on the bike at the same time so his job is simplified to a great degree. It more or less eliminates the precision timing and sense of the bike?s pitched-forward attitude that it takes to do it the other way. He approaches the lean, speed, traction more gradually and gets continuous feedback from them.

 

With the straight line method the rider has to also determine by his feel and prediction just how quick his flick into the corner needs to be to maintain the suspension compression smoothly. A lot of multi-tasking is going on here.

 

When you realize that this all has to be figured out just BEFORE he does it you see why the two methods are so different.

 

Here is another way of saying it. The trail braking method privides the rider with feedback as he transitions and the straight line method doesn?t allow you feedback until after you already committed and completed it and there ain?t no fixing it, at least not on that lap.

 

There is a high degree of confidence in yourself and your prediction of the forces and your other senses of speed and traction and your ability to quick turn the bike that are essential before you?d be willing to make this level of commitment.

 

Beside all that, there is another huge benefit to learning the straight up/quick flick style. It provides a rider with valuable feedback about tire traction and cornering loads.

 

When you quick flick the bike with poor timing you get a sudden load on the suspension and the tires. This is the thing that riders get into their heads will make them crash?usually they think they are going to loose the front and go down. They get spooked from that sudden load.

 

The feeling of the sudden load came from releasing the brakes too soon before they flicked it. The front end comes up from the release and then dives again from the flick in. If you break that down you?ll see that the load, while it may have a little higher peak force, wasn?t anymore than they would have experienced if they had made that transition into the turn with perfect control timing. The sudden load came from their error not because it is part of the style of riding.

 

This is another one of those things that can become confusing to any rider. They have simply misidentified the real cause of the sudden loading. It could and often is enough to make riders think that they are going to crash by quick flicking the bike.

 

I think that the facts and the physics of the matter are this: If you had the front tire right at 110% traction and you flicked it in and maintained that load that you would be OK and have a killer turn entry speed. You would not have violated the traction limit of the tire (they like to slide a bit for max traction in any case) and would have learned an enormous amount about traction limits. It?s that commitment thing that makes this

difficult.

 

I have heard schools of thought that say that trailing the brakes is an ?advanced? skill.

I have heard schools of thought that say you will get passed if you don?t learn to trail.

That may very well be true, I don?t know everything. What I do know is this: Once a rider can successfully and confidently do the straight line method; once he can do it with flawless timing and clean seamless transitions and he trusts himself and is willing to make these commitments, learning the trail-in style is a piece of cake. Doing it in the other order is not so easy.

 

Keith

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Wow Keith - That was a great post. You pretty much summed up my experience learning how to brake. Years ago, I thought I was the only person who had difficulty braking, but the more I talk to people, the more I realize that braking is a very misunderstood topic for many riders. I also realized that braking can be a very advanced subject. I copied the post, pasted it in word, printed it and am putting it my "binder" for futre reference.

 

That may very well be true, I don?t know everything. What I do know is this: Once a rider can successfully and confidently do the straight line method; once he can do it with flawless timing and clean seamless transitions and he trusts himself and is willing to make these commitments, learning the trail-in style is a piece of cake. Doing it in the other order is not so easy.

 

I started to experiment with trail braking after I became relatively proficient quick turning. I found it very easy to trail brake and I find trail braking to be easier (than quick turning). But, I feel like I give up way too much entry and mid corner speed by trail braking so I rarely do it (unless I am attacking or defending, or as Paab noted certain turns). I find that if I have clear track in front of me and I am under no immediate threat from behind, the fastest way (for me) through the turn is to finish my braking, quick turn the bike and get on the friggen? gas. It just works.

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Wow Keith - That was a great post. You pretty much summed up my experience learning how to brake. Years ago, I thought I was the only person who had difficulty braking, but the more I talk to people, the more I realize that braking is a very misunderstood topic for many riders. I also realized that braking can be a very advanced subject. I copied the post, pasted it in word, printed it and am putting it my "binder" for futre reference.

 

That may very well be true, I don?t know everything. What I do know is this: Once a rider can successfully and confidently do the straight line method; once he can do it with flawless timing and clean seamless transitions and he trusts himself and is willing to make these commitments, learning the trail-in style is a piece of cake. Doing it in the other order is not so easy.

 

I started to experiment with trail braking after I became relatively proficient quick turning. I found it very easy to trail brake and I find trail braking to be easier (than quick turning). But, I feel like I give up way too much entry and mid corner speed by trail braking so I rarely do it (unless I am attacking or defending, or as Paab noted certain turns). I find that if I have clear track in front of me and I am under no immediate threat from behind, the fastest way (for me) through the turn is to finish my braking, quick turn the bike and get on the friggen? gas. It just works.

I agree Steve, that is a great post, and I saved it as well for future reference.

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Will, you mentioned that you raised your idle from 1000 to 3000. Did you do this purposefully to decrease engine braking? Or to make blipping precisely in order to rev-match while downshifting easier or less likely to cause the rear to hop? What advantages in cornering,etc, have you noticed by raising the idle?

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I started setting my idle high on my 954 becasue the bike has so much drive train slap. Setting the idle high effectively removes "jerkiness" related to the slack in the drive train so when I get on the gas there is very little if any "jerk" or slap from the drive train. Then, I started setting the idle high on my race bike (gixxer 750) even though it has very little slap - or so I thought - and I noticed the bike was much more settled when I start to roll on the gas. Now, I set the idle up on all the bikes I track ride (even the school bikes). I have been testing different RPM's and each of the bikes seems to behave differently at different RPM's, but as an example, the school's ZX9R rides very well with the idle around 3k. Will pointed something out that you have to keep in mind though - if you are riding on a track that has a very tight and slow hairpin turn, be sure that you don't set the idle higher than you are prepared to run through the turn :)

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Will, you mentioned that you raised your idle from 1000 to 3000. Did you do this purposefully to decrease engine braking? Or to make blipping precisely in order to rev-match while downshifting easier or less likely to cause the rear to hop? What advantages in cornering,etc, have you noticed by raising the idle?

The main reason I raise it up so when the rear comes up the wheel doesn't slow down and start chattering. There are other benefits as well like less engine braking, but the best is that the tip in is way better. Tip in is a carburetor term that is from idle transitioning into and through the pilot circuit. While this isn?t totally applicable to FI it does start your roll on from a higher flow and is smother. This condition does help with blipping for down shifts too.

Will

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Will pointed something out that you have to keep in mind though - if you are riding on a track that has a very tight and slow hairpin turn, be sure that you don't set the idle higher than you are prepared to run through the turn :)

Hi Steve

What happened to me was I was used to the engine braking and in it's sudden absents I was going faster than I wanted to. Keep in mind I was racing a ZX9 and while it slowed down smartly there wasn't an overabundance of stopping power ( like the 636 has) and I didn't give myself an adjustment session, I just went out and flew into the corner as fast as before and couldn't use more brake because I was already using it all.

Will

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The main reason I raise it up so when the rear comes up the wheel doesn't slow down and start chattering.

 

Will,

 

You may have just answered a question I have been having. I noticed that about the same time I started raising my idle that my rear tire stopped chattering under heavy braking and down-shifting. I never made the connection.

 

So, what is the deal with the jerk in the drive train? Is this all fuel related or is there something else going on causing the slap? In my Honda, it is really, really bad. At lower idle speeds, if I tip the bike in to full lean angle and then try to smoothly get on the gas, I get this big jerk - and it is realy unsettling. After I started raising my idle, the jerk went away and now I feel much more confidant getting on the gas without the fear of busting the rear tire loose at full lean.

 

Steve

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Will,

 

 

So, what is the deal with the jerk in the drive train? Is this all fuel related or is there something else going on causing the slap? In my Honda, it is really, really bad. At lower idle speeds, if I tip the bike in to full lean angle and then try to smoothly get on the gas, I get this big jerk - and it is realy unsettling. After I started raising my idle, the jerk went away and now I feel much more confidant getting on the gas without the fear of busting the rear tire loose at full lean.

 

Steve

Hi Steve

Im guessing you don't have a power commander and haven't remapped your bikes. It's the same deal as with carbs, to meat EPA they must set them up so lean they will barely run. You need to go to a good dyno man who can fatten the bottom of the mapping up and then it will smooth out. By raising the idle you are putting the bike into a different spot in the mapping, one were it runs better apparently.

Will

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Got it - That must be why my GSXR is so much smoother than the Honda (the GSXR has a Power Commander with a map from Spears' on it but I have not yet put a power commander on the Honda).

 

Thanks,

 

Steve

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so far what i've noticed about trail braking is that if i feel i have to trail into the corners, i haven't found the appropriate turn in point to quick flick. i rework the corner a bit, and usually am able to find a line that gives me a smoother, more comfortable line/flick-in with no perception of impending lack of traction. i would like to clear something up, or at least put my input into it... i think there is a difference between "trail braking" and "braking during corner setup". i think the former is "braking while leaning the bike, at whatever constant rate, into it's final lean angle", and the latter is "braking while you make slight adjustments to get to your turn in point, where you let off the brakes and make your final turn". i think from that we might be able to simplify things better by saying that trail braking is simply: having the brakes applied AFTER you have passed your turn in point." there is a difference between bending the bike a little to get to your turn in point, and flicking the bike over to turn when you are actually entering the corner. the best demonstration of this is in the decreasing radius corner, the rider must often make his final turn point be so deep into the corner, that it's not possible to get to it without bending your turn entry approach line. i'll be very interested to see what y'alls opinion is to my opinion and what i've noticed riding :)

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oh yeah and the driveline lash is also from small clearances between gearteeth, chain/sprocket teeth, etc. and is more than just where your engine is running in it's powerband. the powerband part has more to do with how easy it is to control your engine, and how easy it is to open the throttle at a rate which initially allows the engine to spool up at a rate that lets the clearances between teeth and whatnot gradually diminish to the point of full contact, at which point any amount of throttle can be applied with no lash. you can test this out by cruising along a straight road, neutral throttle, then chopping throttle and cracking it open. i'm sure that you will find there is some lash involved. it is much more noticable on older bikes where the driveline has been well worn. it doesn't matter what rpm range you are at, if you go abruptly from positive throttle to negative throttle, or vice-versa, there will be lash. it will be harder to detect on a newer bike that has closer tolerances in the driveline than an older model that was looser to begin with and has become more so as miles have taken thier toll.

 

i'd be interested to know what years your gixxer and honda are, Steve.

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