300ex with 400ex a-arms

[jermill79]

does anyone know how good 400ex a-arms will work on my 300ex? will it cause any problems with the travel of the a-arms and the stability of the quad and if you have any pic of what it look like please send them to me my email is jermill79@yahoo.com

[redrunner]

do a search on the topic, tons of info.;)

[ZSK]

Bumpsteer like a mofo, save up for +2's

[frozenh2o]

Here's a thread to when I did it to mine.

http://www.exriders.com/vbb/showthread.php?s=&threadid=32542

[414tinner]

I have been wanting to do this same thing to my 300ex. Does anyone know if the stock length shocks will fit this set up. I was going to get shocks for 300ex +2 a arms for this setup. Any help would be great. Thanks.

[300exOH]

Do yourself a favor and research the subject before doing it. The 400ex arms will fit but they will not work correctly. I tried it for a while on mine and found the bumpsteer was too much. My arms would get tired much faster because I was fighting the steering constantly. Jeff and Bradley's past posts on the subject explain it all. You are better off with +2 aftermarket arms meant for the 300ex along with a shockmount bracket and some custom shocks(basically a long travel setup).

[redrunner]

We should have an alert posting everytime this comes up!!:eek2:


Here's a pic of +2+1 300 arms and a relocator, I did this 300 set up twice once with the works shocks and then again with some longer length Elka's. Do it right and it is a great set up.

check this thread also.
http://www.exriders.com/vbb/showthread.php?s=&threadid=112424

[sjc115]

The 400ex a-arms will work.

Bumpsteer is caused by the relation of the tierod pivot points, the ball joint locations, and the a-arm pivot points. The geometry between all of those determines how much or how little bumpsteer your machine has. Any time you lengthen the a-arms you are going to change the bumpsteer regardless of which quad you have, that is a fact proven by geometry. If you don't change the location of the pivot points, you have not reduced bumpsteer. Does the bumpsteer change with 400ex arms on a 300ex? YES. But it changes on ANY quad when you go to longer a-arms and will change even if you buy +2 300ex a-arms.

I keep reading posts that say 400ex arms won't work, but nobody has given any valid reason as to why. In addition to that, there are many people out there using them (including me) that are not having any problems. I have not measued bumpsteer on my quad but when I compress my front suspension, visually I do not get much more bumpsteer than I had before, and it has not made a noticable difference out on the track.

Also, I have seen some posts that say the tie rods hit the arms at full lock, but I have not experienced this at all.

Of all the people who say it does not work, somebody please post a valid reason with proof (i.e. a picture, a drawing, etc.) as to why. Maybe between all of us here we can get some resolution to this subject.

[bradley300]

there has been plenty of resolution on the subject, do a search! i'm tired of typing this crap 10 times a week

[frozenh2o]

I agree with sjc115, how about some measurements? Does anyone have the data? It certainly isn't difficult to measure bump steer. If nobody has bothered to measure it, I'll do it on my qaud with the 400ex arms, if someone else can do it on a stock 300ex. Then we'll know. No measurement=no knowledge.

[sjc115]

bradley300: Apparently I have offended you by asking somebody to come forwrd with some good scientific info. That was not my intention. I have done searches on this subject and have found nothing that gives good evidence that it won't work (along with the fact I have done it and it worked fine). Just people with seat of the pants observations (much like mine). What I was suggesting is we need is somebody who has the time and is good at doing research to come up with some hard evidence.

[300exOH]

Don't you think some of the top riders in GNCC sport class would be running the 400ex front end if it worked properly? They have measured and tested the setup and have found it isn't a good setup. The issue is mostly with the tie rod angles and the positioning of the mounts on the steering stem which causes excessive bumpsteer. Also the shape of the a arms don't work properly with the position of the mounts on the 300ex frame which may allow for a change in camber/castor through the suspension travel.

[ZSK]

Exactley what 300exOH said. The steering stem position allows the excessive bumpsteer. The tie rod angles are all wrong, the vertical is ok, it is the front to back angle. On a 400ex they are angled, on a 300 with 400 a-arms the tie rods are straght. I rode a 300 with 400 a-arms for 2 years and ONLY AFTER a steering stabilizer did the bump steer go away. With the stabilizer turned up all the way it was still the same as a stock setup. The angle of the tie rods will also allow the tie rods to bend when a sever load is put on it, hitting a stump, tree, or monster truck tire:mad: . I bent 4 tie rods with that setup and through the same terrain I have yet to bend a tie rod on my 400ex. The tie rod ends will hit the bottom a-arm at full tilt. If you try to turn the tie rod end over and mount it the way it is on a 400ex you'll bend a tie rod even quicker. The front end is very twitchy on any terrain. With hard pack being the worst. The a-arms will bolt up no problem, the brake lines still reach, the tie rods bolt in fine, that doesn't mean the setup works. For the cost you can pick up the 400ex a-arms shocks and tie rods, make the bracket. Ride it hard, IE race speeds, through rough terrain. Remove the setup and put on +2 300ex a-arms, custom shocks and the bracket. That will instantly produce a better setup for you to realize.

[redrunner]

Guy's do you believe this!!!!

Bradley, Scott let's give up! They Win!!!

[ZSK]

How many times have people searched and never found anything? Read this thread: http://www.exriders.com/vbb/showthread.php?s=&threadid=88139&perpage=15&highlight=400ex%20aarms%20on%20300ex&pagenumber=1 I found that within 1 minute of searching and that explains directly why this is a bad idea.

[bradley300]

Originally posted by sjc115
bradley300: Apparently I have offended you by asking somebody to come forwrd with some good scientific info. That was not my intention. I have done searches on this subject and have found nothing that gives good evidence that it won't work (along with the fact I have done it and it worked fine). Just people with seat of the pants observations (much like mine). What I was suggesting is we need is somebody who has the time and is good at doing research to come up with some hard evidence.
sorry, not offended, just getting tired of this argument, jeff@quadshop and i have run this topic into the ground and still people are convinced we dont know what we are talking about. we have done all the measuring, riding and evaluating and designed a better set up. everyone that had a 400ex front end and switched to our design swears ours is way better than a 400ex frontend

[frozenh2o]

Well I'm going to know the answer, because I bought Redrunner's 300ex +2 Burgard arms to replace my 400ex arms. I think the 400ex swap was an improvement over stock for fast desert trail riding. I can expect a huge improvement from the Burgards, right?

[300exOH]

I have the burgard +2's with custom shocks and the shockmount bracket and I think it's awesome. I had the 400ex front end before and didn't like it. You should notice a difference right away. It isn't as twitchy, there's much less bumpsteer and I also think it has a better turning radius.