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1fst400
01-23-2007, 03:09 PM
Does any one here know how much weight is on each of thier tires..


My quad seems to have steering issues. It pushes real bad. Im thinking due there not being enough weight on the front tires and to much on the rear.


Its not bad for dirt, I can deal with it. But on ice, omg, its pissing me off. I cant barley get it turned, once its wiped out its fine.

I dident have time today, but tomorow im going to set my quad up on the scales to see where im at.


So far I have tired. stifening the rear shock and softening the fronts. it helped some. But its still bad.

Pappy
01-23-2007, 03:13 PM
Just a geuss here.....


but when you installed the 450r engine into the 400ex frame, you changed the weight bias(to the rear of centerline) and that is why you are noticing the light handling front end.

1fst400
01-23-2007, 03:14 PM
well no kidding. im just trying to figure out how to fix it. cant be to much diffrent than when ppl put crf motors in.

Pappy
01-23-2007, 03:33 PM
a second geuss as to a fix would be a shorter swingarm.

ss440ex
01-23-2007, 03:48 PM
Try taking some pre load out of the front shocks..

1fst400
01-23-2007, 08:26 PM
Originally posted by Pappy
a second geuss as to a fix would be a shorter swingarm.


hmmm..... Wouldent a shorter swing arm put the weight more on the rear tires?



I backed the prelaod off all the way on the front shocks.

1fst400
01-23-2007, 08:44 PM
after throwing around the thot of moving the motor foward....


I decided that im going to try putting some lead weights up on the front of the frame. Its not the best set up. but It will only be for riding out on the ice, so I dont see what 10lbs will hurt other that power. Right??

duneflyer1
01-24-2007, 09:40 AM
That would have been my fix for it, if it doesnt affect you for dirt. Maybe a larger gas tank as well? I assume there is no jumping in Ice racing? I live in Yuma, AZ, and dont even know what snow is, let alone ice, hence the question.

1fst400
01-24-2007, 09:48 AM
nothing more than mabie a cupple feet of air. Im just messing around, not racing in the winter.


Here is a scale sheet. This is w/o rider

1fst400
01-24-2007, 09:50 AM
forgot pic:blah:

1fst400
01-24-2007, 09:53 AM
with me sitting. on the seat.


Keep in mind. these are somewhat aprox. I dident completely level out the scales. and I have skrews in my tires. so that could affect it a little also. But I'd give it +- 2lbs acuracy.

1fst400
01-24-2007, 09:56 AM
now if I could find out what a fourhwheeler has stock I could go from there.

If no one on here knows. I can go grab the GF's 400ex sometime this weekend. For comparison

Pappy
01-24-2007, 09:57 AM
i wonder why the right front is higher then the left?

1fst400
01-24-2007, 10:03 AM
This is with the preload backed off on the front shocks quite a ways.

1fst400
01-24-2007, 10:05 AM
Try to ignor the big mess. Im in the process of rebuilding my race car motor and front end.

1fst400
01-24-2007, 10:08 AM
Originally posted by Pappy
i wonder why the right front is higher then the left?


Im not shure. If you look... The RF and LR have 52% of the weight. That means the LR and RR have 48%.


It could be many things I guess. Steering turned just a tad. One tire bigger than the other. loose hub. Bent axle or swing arm. Bad swing arm bearings.

TBD
01-24-2007, 10:21 AM
I have a question for you 1st400. First is what width arms are you running and are they 1" forward by any chance? 400EX's have always had a problem with pushing in the front because of the wieght bias problem. You could go with a 1" longer swingarm (not shorter). If your arms are 1" forward get rid of them. Is the caster correct or are the arms caster adjustable.

As for the difference in wieght from side to side it's probably what you said. Tire size, stiction in bushings or bearings or maybe even the preload bieng different in the front shocks. Even though the adjusters might be in the same place you could still have a difference in springs that could cause that.

Pappy
01-24-2007, 10:27 AM
Originally posted by TBD
You could go with a 1" longer swingarm (not shorter).

Thats why I pm;d you...lol

every 400ex ive run with an extended swingarm pushed badly, even with + 1 or +0 arms and wasnt 100% on if the shorter arm would help.

1fst400
01-24-2007, 10:32 AM
It would have helped if I put up all my info. My bad. dono if the brands matter but it cant hurt.


Im running a
-LSR +1 1/2 swing arm possible a 1 1/4" I cant remember.
-+4 axle durablue
-+3 LSR a-arms. Non caster adjustible.
-Stock rear shock with elka zps rebuild, stock linkage
-Elka front shocks, they are zps, and have 4 springs including the zps spring

TBD
01-24-2007, 10:40 AM
Originally posted by 1fst400
It would have helped if I put up all my info. My bad. dono if the brands matter but it cant hurt.


Im running a
-LSR +1 1/2 swing arm possible a 1 1/4" I cant remember.
-+4 axle durablue
-+3 LSR a-arms. Non caster adjustible.
-Stock rear shock with elka zps rebuild, stock linkage
-Elka front shocks, they are zps, and have 4 springs including the zps spring
So the arms are not forward? I think Lonestar built there swingarms plus 1.25". How is your ride hieght (race sag). Is the attitude of the quad nose up or level. This can make a difference biengs that you have no caster adjustability. By running the quad up a little in the front you would have more positive caster making the steering slower. By running it level or down just a little in the front would make less positive caster making the steering quicker and giving you a little bit more forward bite (less push).

TBD
01-24-2007, 10:43 AM
One more thing. Softening the front end doesn't always work. If you make the front tooo soft then you will actually lighten up the front end making it worst as far as getting forward bite.

1fst400
01-24-2007, 11:03 AM
Thanks for the help so far. I completely understand what your saying about the caster.

1fst400
01-24-2007, 11:09 AM
I spoke to soon on the caster adjustible.. They are, I was confused because my last set of a-arms were not.

So YES they are caster adjustible. This should help me out some


However how much do you think I should adjust it..

I want the top of the spindle to be going twards the rear of the quad slightly.. Correct?

TBD
01-24-2007, 11:27 AM
Originally posted by 1fst400
I spoke to soon on the caster adjustible.. They are, I was confused because my last set of a-arms were not.

So YES they are caster adjustible. This should help me out some


However how much do you think I should adjust it..

I want the top of the spindle to be going twards the rear of the quad slightly.. Correct?
Yes, the top of the spindle should be towards the rear always. There are a few exceptions to this but they pertain to large cars. If it were me I would first get your race sag where you want it and then I would run -1.5 degrees to -2 degrees for camber. For caster I would start at +5.5 - +6 degrees caster. There is a point in which running lees caster to try to get more forward bite will stop and all you will be doing is ridding a quad that the steering is too quick and becomes twitchy. One more thing, I would set the toe at 1/4" toe in in the front. All the measurements that I listed above should be taken with the rider on the quad so you will need a second person for this part.

Rootar
01-24-2007, 12:58 PM
i ran into the same problem after i switched to a PEP bigbottle rear shock and link compared to my stock noleen rebuild and stock link the PEP works amazing every except it hooks up WAY to much, holeshots are simple now but turing is a ***** and big one, the front elkas were setup so diferently compared to the way the pep rear was setup, right now derisi is fixing my front elkas to work like the rear pep i had adjsuted everything

im running
+2+1 LSR race arms (3/2 wheels)
+1.25 Janessen Swingarm
PEP big bottle rear with custom baldwin link
elka elites front shocks

you might want to check for somehting like this picture :huh thats all the swing arm right there and i snapped my chainroller MOUNT right off the bottom rail of my frame:ermm:

400exrider707
01-24-2007, 01:20 PM
I've noticed a lot on the 450Rs that putting arms on that are +x +1 forward push WAAAAY more than ones that are +x+0.

TBD
01-24-2007, 01:24 PM
Originally posted by 400exrider707
I've noticed a lot on the 450Rs that putting arms on that are +x +1 forward push WAAAAY more than ones that are +x+0.

I agree. It is crazy to move the arms forward when you already have a quad that pushes. The longer swingarm was a plus.

400exrider707
01-24-2007, 01:39 PM
Originally posted by TBD
I agree. It is crazy to move the arms forward when you already have a quad that pushes. The longer swingarm was a plus.

Yes, but for some reason so many people still buy +1 forward arms. I think the only quad that I have ridden on that felt better with +1 forward arms was a banshee, and I've been told that they help out a lot on 300ex's

1fst400
01-24-2007, 02:48 PM
thanks for the info. Im going to try all that tomorow and test er out.


Im not shure how im going to measure the caster. Probly just a angle finder. not the moast accurate tho, I will have to get one of my buddies to come over and sit on the seat.



But do thoes weights look okay?

Rootar
01-24-2007, 05:00 PM
Originally posted by 400exrider707
Yes, but for some reason so many people still buy +1 forward arms. I think the only quad that I have ridden on that felt better with +1 forward arms was a banshee, and I've been told that they help out a lot on 300ex's

i got mine for free:o cant complain when theyre given to ya...

my wheel base is 51 inches with these arms and swing arm i think a stock 400 is like 48.75 or something around there

btw they originally made plus forward arms for the older 250r's to gain wheelbase for straight line stability with out losing traction from a longer swingarm ;) my dads first cousin has a 250r he used to race flat track way back in the day and the plus forward arms were the "hot setup" he gave me these arms because they were some of his spares from way back when and i jsut bought new joints and heims and all that

ZSK
01-24-2007, 05:52 PM
Possibly overlooked but, have you tried removing some of the rear studs?

Rootar
01-24-2007, 08:06 PM
Originally posted by ZSK
Possibly overlooked but, have you tried removing some of the rear studs?

i was still here trying to figure out some way to help but that right there sounds like pretty logical idea less rear traction means it wont pick up the front end as much so it should turn much better the more studs you remove but youll have to find a middle between traction and turning i would think i remember reading about how those ice racing jeeps run less studs in the rears and more in the fronts so they can turn really precise.

400exrider707
01-24-2007, 08:20 PM
Originally posted by Rootar
i was still here trying to figure out some way to help but that right there sounds like pretty logical idea less rear traction means it wont pick up the front end as much so it should turn much better the more studs you remove but youll have to find a middle between traction and turning i would think i remember reading about how those ice racing jeeps run less studs in the rears and more in the fronts so they can turn really precise.


Actually after looking at your pics again you have hardly anything in your front tires!!! Put some more studs in the fronts!!!!

1fst400
01-24-2007, 08:25 PM
there is plenty in the front tires. look again.

400exrider707
01-25-2007, 05:42 AM
Originally posted by 1fst400
there is plenty in the front tires. look again.

Im looking...looks like they could use some more IMO.

1fst400
01-25-2007, 10:09 AM
I changed around my caster and LF camber today. It straigtened some stuff out nicely.

The camber isnt the same on both sides because with one full turn of the ball joint it adjusts it to much

1fst400
01-25-2007, 10:13 AM
and here is what I changed it from. same as the other day, I just added the caster and camber info. Ignor the blood I cutmyslef while loosening a nut.
I also put my preload back to where I had been running it for mx.

400exrider707
01-26-2007, 07:53 AM
If you add the two total weights up... they are different!? Maybe Im reading it wrong or something though!? Your first one is 605, and the second is 590? Or is that not correct way to add that up?

1fst400
01-26-2007, 11:23 AM
when you do it one person. you turn your head and write the number doun. Just the weight transfer from moving your head or hand to a diffrent spot on the paper changes the weights. so unless you have 2 ppl, one to sit still and the other one to write stuff doun that is just what you get.


if you ad up the front and rear it isnt that accurate because I had to bend over and push a button to switch it. But Left to right shows on the screen at the same time, so that will be more accurate.

Needmorehp
01-29-2007, 12:57 PM
Ice Racing for many years. You may need more studs in front. Check the alignment of each stud? This will add or subtract traction, Also what air pressure are you running? We run 19" Razors on the 4-strokes, and about 4lbs. of air. even more studs, and 18x9.5x8 Rear Cheng Shin Ice Tires really cheap, but work the best, Big factor. You also want each tire front L/R to have even balance with a swaybar, I don't see one. Don't add weight, will just mess things up. Toe in about 1/4" and slight camber, not exactly sure of degree. Look at an Indy Car? It does work. These are a few things.

Hope this helps.