Ability to lug....


50 replies to this topic
  • bobpara

Posted May 15, 2013 - 11:54 AM

#21

That's right, a larger sprocket will give more top speed, less lugging
The reverse is true with a smaller one.
You also have the problem of having to shift every 2 seconds if you gear too low (too small of a front sprocket)
When you have one slightly taller ratio its kind of nice in the woods when you rarely need to shift....its like having an automatic trans!

Kinda odd, that old DR had so much internal mass (just like having a huge, heavy flywheel) I could get away with gearing a bit tall and it would still lug nicely.
This WR seems to have a flywheel made from paper. Its really easy to stall when going slow in a tight section in the woods.

Funny. A good woods bike is a different animal than a good motocross bike (which is where the WR came from).

  • KennyMc

Posted May 15, 2013 - 12:14 PM

#22

That's right, a larger sprocket will give more top speed, less lugging
The reverse is true with a smaller one.
You also have the problem of having to shift every 2 seconds if you gear too low (too small of a front sprocket)
When you have one slightly taller ratio its kind of nice in the woods when you rarely need to shift....its like having an automatic trans!

Kinda odd, that old DR had so much internal mass (just like having a huge, heavy flywheel) I could get away with gearing a bit tall and it would still lug nicely.
This WR seems to have a flywheel made from paper. Its really easy to stall when going slow in a tight section in the woods.

Funny. A good woods bike is a different animal than a good motocross bike (which is where the WR came from).


Might be some jetting issues going on...

  • GP1K

Posted May 15, 2013 - 02:49 PM

#23

So gearing isn't the only issue here... Krannie touched on it on the first page. The deal is your old DR350 and your new WR450 are different animals. The 'old school' thumpers like your DR, XRs, etc are quite a bit different than modern thumpers. All the engine internals were heavier, creating more rotating mass for better lugging (kinda like a heavier flywheel does). As such they revved slower, and revved out sooner. Their torque/HP curves would be more on the torque side than HP side. All these things combined made them better at lugging. Modern thumpers have much lighter motors with lighter internals. They are MUCH faster revving, and rev to the moon compared to old ones. And they make a lot more horsepower, but at higher revs. This is obviously not ideal for lugging.

So yeah, there is no real 'fix' there, it's the nature of the beast. Sure you can play around with gearing and mitigate it to some degree, but that won't really solve the problem. A Rekluse can keep it from stalling, but doesn't change the nature of the power delivery itself. It merely slips the clutch for you. The real 'fix' here is you're going to need to adjust your riding style a bit to accommodate the new bike. This isn't a perfect analogy, but think of riding your old DR vs your WR like riding a 4T vs a 2T. You can't lug a 2T like a 4T, you have to rev it more.

  • Krannie McKranface

Posted May 15, 2013 - 06:03 PM

#24

When you gear down, the bike will lug WORSE because your throttle response gets more touchy, and it's more dificult to hold a low rpm (the DEFINITION of lugging).
When you gear up, you now have softer throttle response, making it much eaiser to lug the motor.

If you are talking about more torque at a given rpm, lower gearing accomplishes this.
If you are talking about lugging the motor, keeping it in a low rpm so you can improve traction and have better throttle control, GEARING UP, is what you want to do.

I gear up all my bikes (14/50 or higher), jet them perfectly, and they will run at 1800 rpm up hill.

If I were to take the same bike, and gear it 12/50, it would be going too slow to get over obstacles, without up shifting, or going up into a much higher rpm. But THAT is NOT lugging.

  • n16ht5

Posted May 15, 2013 - 06:04 PM

#25

After coming off riding XR's I can tell you that a Rekluse would solve your problem right off the bat without having to adjust very much. Set the engagement very low and very hard.

  • spomey

Posted May 17, 2013 - 04:37 AM

#26

When you gear down, the bike will lug WORSE because your throttle response gets more touchy, and it's more dificult to hold a low rpm (the DEFINITION of lugging).
When you gear up, you now have softer throttle response, making it much eaiser to lug the motor.

If you are talking about more torque at a given rpm, lower gearing accomplishes this.
If you are talking about lugging the motor, keeping it in a low rpm so you can improve traction and have better throttle control, GEARING UP, is what you want to do.

I gear up all my bikes (14/50 or higher), jet them perfectly, and they will run at 1800 rpm up hill.

If I were to take the same bike, and gear it 12/50, it would be going too slow to get over obstacles, without up shifting, or going up into a much higher rpm. But THAT is NOT lugging.


I guess we may have different definitions of lugging. What i wanted my bike to do was.....1) pull the front wheel very easily, to cross logs and such at slow speeds. 2) move very slowly through very rocky and technical terrain without stalling or having to slip the clutch. 3) still maintain 70+ mph on the roads... the 12/52 gearing did that...no doubt about it.

I dont understand gearing larger in the front helping low speed technical riding (the reason I want it to "lug") simply put...i couldn't get it not to stall so i was wearing out my starter on really nasty climbs.

I dont have a problem with the quick throttle response maybe its my weight (255+ gear). I guess my question is...Have you ever tried gearing down the newer four stokes? Because what your describing simply didnt work for me not at all. One tight steep slow section and when the motor RPM drops = stall....drove me crazy, admittedly i SUCK at fine clutch control and a slipping clutch is a bad thing in my thoughts.

*****Warning****** I was warned from the local Yamaha dealer that the 12T up front was too low and could actually break the chain and potentially that could break my cases. So far so good. *****Warning******

as for shifting all the time...well it is a WR (wide ratio) and maybe i am not so picky about changing gears but it is NOT problematic in any way....IMHO....I mean C'mon the engine revs super high to allow for a large change in speed per gear...

to me its the best mod to my bike, for what i bought the bike for...high elevation technical riding.

SO.....I recommend spending $15 on a 12T front sprocket and see for yourself.

  • KennyMc

Posted May 17, 2013 - 05:21 AM

#27

Well, really what you want the bike to act like is a trials bike. The ability to go slow over/around/through obstacles with the RPMs still high enough as to not stall the bike. By definition, if the bikes RPMs are that high, the bike is not "lugging". That is where I think the misunderstanding is coming into play.

A bike that is "lugging" is where the RPMs are slow enough that the bike is coughing and sputtering and about ready to stall without either a quick pull of the clutch or snap of the throttle.

  • n16ht5

Posted May 20, 2013 - 08:02 AM

#28

I guess we may have different definitions of lugging. .........


........ One tight steep slow section and when the motor RPM drops = stall....drove me crazy, admittedly i SUCK at fine clutch control and a slipping clutch is a bad thing in my thoughts.......




Here lies the problem. you need to learn to use the clutch. You should always have one finger on it and be using it to clear obstacles. Watch pro trials riders and you will see how it works. I have a rekluse but I still use the 1 finger override lever all the time.

On 2T's and small HP bikes I will actually ride the rev limiter and feather the clutch instead of using just the throttle on hillclimbs and tough obstacles.

I gear up like Krannie does, makes for a lot less shifting since the spread is wider.

  • SLC18T

Posted May 21, 2013 - 06:57 AM

#29

Great explaination spomey. You have the same thoughts as I do. Coming from a KTM RFS engine with torque to the moon, I am wishing the WR engine had more bottom end grunt like the RFS. They are different engines for different purposes. I understand that. Just wishing I could have KTM power with Yamaha reliability.

  • beezer

Posted May 21, 2013 - 07:05 AM

#30

If you stall a WR450 it's your fault not the bikes.

The motor is the best part of the bike.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • wrwest

Posted May 22, 2013 - 03:22 AM

#31

The secret to riding tech with any bike is to get used to riding with as little clutch use as possible.
The abuse of the clutch overheats the oil and then rad fluid boils.
slipping the clutch is also a contributing factor to stalling the bike.

I have gone through the clutch abuse unfit fase so its not just thumb sucking.

Learn to ride over obsticles and check out these tips on Youtube . Search THE OFFROAD FANATIC

  • spomey

Posted May 22, 2013 - 06:18 PM

#32

The secret to riding tech with any bike is to get used to riding with as little clutch use as possible.
The abuse of the clutch overheats the oil and then rad fluid boils.
slipping the clutch is also a contributing factor to stalling the bike.

I have gone through the clutch abuse unfit fase so its not just thumb sucking.

Learn to ride over obsticles and check out these tips on Youtube . Search THE OFFROAD FANATIC




now someone agrees with what i'm talking about. I refuse to burn my clutch so i substitute gear reduction it works very well. that being said.....understand i do my riding at 7-10,000 ft. power levels are decreased at that altitude...and quite frankly so are the human power levels, I simply don't have the internal reserves to be aggressive at all times.

  • grayracer513

Posted May 23, 2013 - 01:28 PM

#33

With the low gear that a WR already has, I'm surprised it's this big an issue, but there absolutely IS a cure. Installing a Rekluse is tantamount to replacing your clutch with a torque converter. No one I know ( and I know some really talented people ) is capable of modulating the clutch as well as the Rekluse does by itself. Of the 3 they offer, the Z-Start Pro is the best choice for off-road applications because the engagement is more linear and refined than the other two.

Gearing down affects engine RPM in gear at any certain speed on a percentage basis directly related to the percentage by which the overall ratio is changed. If your minimum workable RPM is at too high a speed, let's say 12 MPH, gearing it down 10% will put you at the same RPM at 10.8 MPH. The trouble is that it will also take your, let's say, 90 MPH top speed down to 81, and raise your engine speed by 10% at any speed you normally ride.

One other point with carbureted engines. If you are having a problem with sudden stalling as the throttle is chopped from medium/high loads at lower RPM, it i susually because the idle mix is set too rich. It normally gets that way when people fatten the mixture up to eliminate all traces of any decel popping, or when incorrectly richening the pilot to improve throttle response when the problem lies elsewhere.

The only other cure is the one my son is found of using: go faster :excuseme:

  • NitrousR1

Posted May 23, 2013 - 03:38 PM

#34

You really need a flywheel weight, this will reduce slow speed stalling and the bike will lug along better at low rpm

  • wrwest

Posted May 24, 2013 - 05:06 AM

#35

There are no flywheel weights for the WR but a steel clutch basket might be an option if more rotational weight is needed.

I use a 13 standard front with a 52 rear and found this combination to work well for me.

The big problem with riding tech is fitness or a lack there-off .

  • highmarker

Posted May 24, 2013 - 05:18 AM

#36

450 has plenty off idle, learn the long lost art of clutch skill

  • n16ht5

Posted May 24, 2013 - 06:40 AM

#37

The secret to riding tech with any bike is to get used to riding with as little clutch use as possible.
The abuse of the clutch overheats the oil and then rad fluid boils.
slipping the clutch is also a contributing factor to stalling the bike.

I have gone through the clutch abuse unfit fase so its not just thumb sucking.

Learn to ride over obsticles and check out these tips on Youtube . Search THE OFFROAD FANATIC



TI can't stand squids that tear up switchbacks and obstacles because they spin their wheels instead of using the clutch and momentum.

  • stevethe

Posted May 24, 2013 - 07:11 AM

#38

I know the problem I had with mine at one point was the (ACV) air cut off valve. If the bike is made to breath more air you can overcome this valve. So the third blip of the throttle the bike would cough and stall. Not very plunk-able.

There are also many carb mods that are possible that help at off idle and make a big difference.

  • wrwest

Posted May 25, 2013 - 12:48 AM

#39

TI can't stand squids that tear up switchbacks and obstacles because they spin their wheels instead of using the clutch and momentum.


So you saying I am a Squid?

  • throttle violence

Posted May 25, 2013 - 01:42 AM

#40

the reason wr450 wont lug is that the camshafts and much bigger(more lift) and higher compression all the things that dont like to run at very low rpm (thats why hi performance street cars with massive camshafts run huge stall converters) your easiest fix is to put a less agressive camshaft and lower compression piston but you will loose power OR just learn to ride it. fly wheel weights will do nothing and changing gearing as well wont make it better the problem is in the cams and compression. get a recluse kit if you really need it.




 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.