This will be updated as we get more questions and answers in the “Ask the Experts” forum!
Quad Parts - Mechanical
Our Apex’s weigh in about 290lbs and our frames are made of steel. If i was to have an aluminum frame made, any ideas on what the frame would weigh? Does any body know of someone locally that’s capable of jigging one up?
Answered by Daddio: I know a couple guys that could, but you would end up with a $5000 (or more) frame. If you did a hundred or so frames, then the price per frame could be cheaper. Arland Lehman tried it based on 250R geometry, and he couldn’t even make it cost effective. There is a lot more engineering that would go into building an aluminum frame, than just replacing the steel tube with aluminum. Then you would have to heat treat it when you are done.
Then, it would be illegal for any class except “open”, as it wouldn’t be a production frame any more. Good idea though.
Answered by Backcountry: Aluminum doesnt have the mechanical properties that steel does- fatigue, stiffness, strength, etc- all critical factors used in the design. Most OEM frames are made from a 1000 series steel. Switching to a high strength alloy steel like 4130 will allow you to have a sufficiently strong frame that is lighter. The 4130 is stronger as compared to the 1000 series steel- so you require less of it to have an equivalent strength.
Most aluminum frame ventures have not ended well in an ATV chassis. There is considerable flexural elements in having 4 wheels as compared to 2. An aluminum frame stiff enough to prevent too much flex and subsequent cracking has been problematic. Additionally the weight component of a frame of an ATV is typically around 10% of the total weight. As in a 290# scooter, 29# pounds of that is the frame. Going to aluminum frame may only buy you 4-5 pounds at best.
Skip the billet bling. Strip off the unnecessary crap (parking brake, extra brackets, guards), don’t fill the fuel tank to full capacity for a 3 lap moto, select light(er) weight components- but accept the trade-off: they wont be as durable. To finish first, you must first finish…
How do you get the tank to fit on an 05 with the FCR? The top of my carb hits the tank and won’t let sit where it should. I put my 06 tank on the fix the situation for the time being but I will need to put that back on the other bike soon and I really don’t want to spend the money for a new tank when I know people were using these carbs on Hondas before the 06 was out to steal a gas tank from.
Answered by TCS Motorsports: My Experience has been with using the 06+ 450R carb you will need to use a tank off of a 06 and newer 450R because the carb is a lot taller where the throttle cable and idle adjust are located than on a CRF or YFZ carb. Honda changed the gas tank in 06 to accomadate the FCR carb that came stock on the 06 and newer 450R’s, its a slightly different carb than what they put on the CRF’s.
Instead of having to use the NOSS adapter with the 04-05 airbox and boot, you can use an airbox and boot from an 06+ 450R, to make it mount to the 04-05 subframe you will just need to drill new holes in the mounting tabs or use a subframe off of an 06 or newer which is stronger than the older subframes. The other added bonus of using the 06 and newer airbox is it allows you to use the 06 and newer air filter which is alot bigger than the 04-05 filter.
I want to get new bearings with the new axle. Thought that I would ask before I buy. Tapered Roller Bearing or Twin Row?
Answer from Backcountry:
- Sensitive to preload. When tightening the nut you have to preload them correctly and carefully otherwise you will have problems.
- No dust/dirt seals at the bearing to keep the gunk out, especially bad when you pressure wash. You will have to grease after each time you wash to push (hopefully) the dirt and water out. The outer seal always isnt enough…
Twin row are easy to adjust, have seals, and are plenty strong….
Answer from Daddio:
The twin-row are nice, but twice as expensive, and if you ride in the mud a lot and pressure wash your quad, they don’t last any longer in a YFZ.
I tried the taper bearings, and they are nice, and the Rad mfg one comes with a wave washer to help set the pre-load, but you still have to take them apart all the time and clean them. With the tapered bearings if they spin real smooth and easy, you don’t have enough grease in them.
Help me if you can. Is it better to increase the rear gear or drop the front gear?
Answered by Daddio:
It depends. Increasing the rear = less ground clearance. Decreasing the front 1 tooth = increasing the rear approx 3 teeth, and sometimes that’s too much. The smaller the front sprocket, the tighter the radius that the chain has to go around, and the more likely it will be to jump ship.
You should have a selection of gears, anyway. Not all tracks require the same gears.
I have been noticing that my quad has a ton of body roll in the corners. I have changed the pressures in the Evol and the main chambers, but nothing is working. The compression and eveything is fine but it just dives really bad. Anyone know why or how to fix it?
Daddio: Your rebound dampening in the rear shock might be soft. You may need to raise the front of the chassis or lower the rear.
Backcountry: If I have the main chamber pressure too low it will roll in the corners.
Quad75: From what I have learned with testing with the Fox guys: There are two ways to help get rid of body roll. One is increase pressure in the Evol chamber, if you have tried this with small amounts, try more. Those chambers are good for 300psi but I have never seen them over 180 on a set of mine. However this will make things a bit more harsh in other areas if you have to go to high with the Evol chamber.
The other is if you have DSC, you can increase your low speed compresion(the one adjusted by with a screwdriver) several clicks and this should help as well, without much adverse affect elsewhere.
RPK: I have been running 200psi in my Evol chamber and higher amount of psi in ride height. Having more pressure in both the chambers seems to help with the all round ride of the shock. To offset this my rebound is slow and compression is low too.
1) are YFZ and YFZ-R shocks the same size? I.E. same length eye to eye? Can I get shocks from either one for what I am looking for? I have seen that the YFZ-R Long Travel shocks are 18 or so inches eye to eye..
2) True/False, and/or your opinion……I am told that ’08 and new YFZ shocks are the way to go?
Answered by Daddio:
1) Stock YFZR shocks are longer than the YFZ shocks.
2) ’08 and newer YFZ shocks will have the softest springs and high/low speed dampening adjustment.
I have been told that if you gusset the frame it makes it too stiff and creates more headaches than just a stock frame. I have never really inspected the current frame to see if there are any issues but since I have a bare frame I am thinking about a gusset kit. I will be getting the bolt on support for the subframe.
How do I remove the bearings from my frame and swingarm?
Answered by Daddio:
The only bearing in the frame is the steering stem bearing. You pull the seals out, then unscrew the bearing holder and top the bearing out.
For the swingarm, it helps to have a bearing puller, but you can press them out.