piranha front spindal hub brake assembly from quad

[bloody knuckles]

 I will be doing the double front  a arm upgrade on my piranha. My question is.
I wanted to buy a quad and harvest the wheels and front hub assembly.. spindal hub disc brakes studs etc... save time and money. Will i need to modify a arms to keep correct geometry.
I dont want to buy quad and be stuck. Whats your thoughts?

[Doug Heim]

IMO I would build the double A-arm plans offered on the Edge site for free.

You can look through the sponcer section on DTS for some of the components needed for the build including the front hub kits.

[Engineer]

I think it will be an uphill battle to save money using parts from a quad.  It will definately take a bunch of time trying to correct the geometry.  And I believe all the quad spindles are cast so they are difficult if not imposible to modify.

If you look at some of the build logs here several people have tried using the quad parts, and it seems to work best if you strictly keep the quad geometry and stick the arms and everything on the side of the buggy replicating the quad mount points.  Trying to hybrid the Edge plans with the quad parts will prove difficult.

If you kept the edge geometry spindles and just used the quad hubs and brakes it might work, but I would look closely at what you were saving before going to the trouble.  Also look closely at the hub offset measurements and brake mounting.

[bloody knuckles]

yes i got the download of russels a arm design.. looks doable. just using the hub brake assembly sounds good. why should i need to look closely at the hub offset measurements and brake mounting. Ahh..clearance issues with the spindal and a arms?  If i can pull it off it may be a good trick

[Rick S.]

My opinion....Russell's a arm design may have the proper geometry, but the shock to wheel travel still sucks. Why go to all the trouble of doing a double a arm front for the piranha, yet not address the biggest problem with it. Put the shocks outboard and use longer stroke.
That design is not quite there yet. Did Russell have a single a arm piranha before he came up with this double a arm design? I doubt it, or he would have known that the shocks needed to go outboard. 

[bloody knuckles]

My opinion....Russell's a arm design may have the proper geometry, but the shock to wheel travel still sucks. Why go to all the trouble of doing a double a arm front for the piranha, yet not address the biggest problem with it. Put the shocks outboard and use longer stroke.
That design is not quite there yet. Did Russell have a single a arm piranha before he came up with this double a arm design? I doubt it, or he would have known that the shocks needed to go outboard.

Can you tell me more. I would prefer to do this right the first time. would you recommend i just stay with original plans?

[bloody knuckles]

I think it will be an uphill battle to save money using parts from a quad.  It will definately take a bunch of time trying to correct the geometry.  And I believe all the quad spindles are cast so they are difficult if not imposible to modify.

If you look at some of the build logs here several people have tried using the quad parts, and it seems to work best if you strictly keep the quad geometry and stick the arms and everything on the side of the buggy replicating the quad mount points.  Trying to hybrid the Edge plans with the quad parts will prove difficult.

If you kept the edge geometry spindles and just used the quad hubs and brakes it might work, but I would look closely at what you were saving before going to the trouble.  Also look closely at the hub offset measurements and brake mounting.

You are right. WAY to much trouble to modify. the hubs have sealed bearings not tapered roller bearings. I stopped there and decided not to proceed any further on idea.

[Rick S.]

I think that trying to make quad hubs and rotors work may be trouble.  Russell's design would be better with longer stroke shocks. The shock mounts on the a arms need to move more outboard. And the upper shock mounts outside and above the frame rails. Similar to the Barracuda. It could probably be done with Fox 2.0 air shocks with somewhere between 5 1/2 to 8" stroke. What parts do you plan on making yourself? What is your budget? I see that Russell's design uses the Edge rack and Barracuda spindles. You might just build Russell's design to plans. The front will be soft, but I'm sure it handles great. You learn it's limits and adjust your driving style to it. Is this your first build?

[bloody knuckles]

yes this is my first build. i don't want to drop tuns of cash on fancy fox shocks just yet, but the outboard shock idea makes plenty of sense. better leverage and quicker response with outboard. more travel too?
are there any plans for this setup or should i just wing it? I plan to keep the cost close to 5k. She wont be pretty but she will run. I will do much of the work myself. I cant do laser cutting or machine work. I'm very good at engines and electrical. Being a mechanic helps

[Engineer]

If you do decide to move the shock mounts around it might be worth dropping the coin on some FOX airs so you can adjust the pressure to suit.

Actually if all you are changing from the plans is the shock location it would not be to difficult to come up with the correct travel shock needed for the new mount location.

If you give me all the necessary dimensions I would cad it up for you.

I thought that Rick changed his shock mounting to a more outboard upper mount even thought he stayed with the single A-arm?

Do the plans show how far the A-arm sweeps up and down in distance or angles?  Or does it just show how to build the mounts?  Is there any setup info like a heigth for the frame at full compression?

[Rick S.]

From what I've seen the plans just cover the mounts.
But I think you're right. This would be easy to do, and do right, once you model up the working assembly view (looking down the axis of the a arm pivots.)
I don't think the Fox shocks are that much more than The Edge shocks.
I did do mine with the single a arms and outboard shocks. Only because I just wanted to improve the shock ratio and was OK with the single a arms. The single a arm Piranha's really do handle nice. I do build the single a arms with outboard mounts, like I have on my Piranha. but I don't sell plans. Mine uses 5 1/2" stroke Fox 2.0 air shocks. The only difference from the Edge plans is the shocks, mounts, and the a arms.
 

[Doug Heim]

I agree with all the above. I do also believe that Russell did have a single A-arm but thats becides the point. It is a huge improvment!

The Edge shocks also are not adjustable in the valving or rebuildable in the sence that your just swapping out the dampening shock itself.

I would build the Double like russel and then run the outboard shocks and also runs the escort rack to save cash.

Fox Airs no matter the size within that range retail for $230 ea. I ship them for free. 5 weeks for delivery.

[Rick S.]

IMO the single a arm with outboard Fox shocks will outperform the double a arm with the inboard Edge 390's. Easier to build also.

[bloody knuckles]

WOW. lots of options, good debate too. I want to keep it simple but still improve on the piranha outdated suspension. I think I will stay with the single front a arm design but change shock placement as rick suggested. (Rick are your arms and mounts for sale?)  I will also do the PIR18 double a arm rear. This will be a good compromise and allow me to buy the fox airs    I may ask engineer for help on measurements later. Thanks for the insight!
oops. I almost forgot... If im not using quad hub assembly then can i source hubs for piranha in the us? or buy from edge?

[trojan]

IMO the single a arm with outboard Fox shocks will outperform the double a arm with the inboard Edge 390's. Easier to build also.

I agree totally!

BUT Russell's Design Parameters were to use edge shocks, that's why he did it that way. Edge shocks, mounted outboard, are WAY too hard.
The implication he didn't understand what he was doing is emphatically wrong.

Another consideration other than complexity with using quad parts is the strength, quad parts are not "buggy" strength. Even some (lots) automotive stuff is not "buggy strength".