RE: Skidoo Rev XP snowmobile hop-up
[b]sokey70[/b] Yeah, the springs which came with the Duratrax shocks were way to mushy and the weight of the body really dropped the shock down below where they should normally sit so I replaced them with the stock springs. The stock springs may be a bit too stiff but they work better than the Duratrax ones (something inbetween the two would work best). Winter is over here for me so I'm busy working on other projects (cars, boats, planes etc.). Please post the some pictures of your design and the components you used - I look forward to seeing it.
Posted on: 3/7/2012 5:52 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10989788

RE: New Bright Nitro Skidoo MXZ Snowmobile
AWESOME! - good work
Posted on: 3/5/2012 7:29 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10987262

RE: Skidoo Rev XP snowmobile hop-up
Also FYI The original stock Rev-XP gear ratio is about 8:1. The mods I made in the early part of this thread reduced that to about 4.2:1
Posted on: 2/29/2012 11:19 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10981706

RE: Skidoo Rev XP snowmobile hop-up
[b]sokey70[/b] If you can get a 40 tooth spur pulley to fit the space, it will most likely work ok. Do you have a pulley in mind with that many teeth which will fit the space? If so, I'd also be interrested in this.
Posted on: 2/29/2012 11:15 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10981695

RE: Skidoo Rev XP snowmobile hop-up
[b]sokey70 and others[/b] Guys Using just pulleys on the Rev-XP will probably not work very well. The space available will not provide enough clearence for a large enough spur pulley to convert the motor energy into enough torque to turn the large track.
Posted on: 2/29/2012 9:59 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10981574

RE: Skidoo Rev XP snowmobile hop-up
[b]Sokey70[/b] The aliminum I used for the prototype is .032. I use this to prototype because I can cut and drill it easily using my dremel. For the real motor mount, I plan on using .025 (thicker) brass sheet. This is thick and strong but cuts easy with the dremel.
Posted on: 2/28/2012 12:31 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10980283

RE: Skidoo Rev XP snowmobile hop-up
Also I read an article in "RC Car Action" this month that Traxxas has now become a sponsor of Snowcross. I'm sure you can figure this out by the name but: Snowcross is the snowmobile equivalent of motorcrosss. Maybe this means Traxxas is ready to take on the challenge of making an RC hobby grade snowmobile!
Posted on: 2/27/2012 3:18 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10978833

RE: Skidoo Rev XP snowmobile hop-up
Regardless that there has been no significant snow fall here, I too have made some progress on my next gen-XP. Here is my prototype - and I do mean prototype - of my brushless 540 motor mount with pulley drive train. The final drive train ratio should be about 4.9:1.
Posted on: 2/27/2012 2:48 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10978781

RE: nitro mod mxz newbright snowmobile
Looks like Hurricane is having great fun. Still no snow here so I'm also reverting to summer projects. Off topic - I just bought a new mini ducted fan jet (EDF) from Great Planes (F86) and can't wait for a calm day to fly it.
Posted on: 2/13/2012 1:43 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10957295

RE: nitro mod mxz newbright snowmobile
Adding a little toe out on the front skis will help prevent some rolling.
Posted on: 2/10/2012 5:16 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10952496

RE: nitro mod mxz newbright snowmobile
[b]Hurricane[/b] Thanks for the pics, are you a machinist? How do you make all those great parts? Also Nitro Tip: In case you didn't know, when you go to run your nitro sled, make sure to keep the motor head warm before you try to start it or you'll have difficulty in cold weather (or start it and warm it up before you travel to your drive site). I use a small (100watt) colman partable electric heater I purchased for about $40.00 from Heartland America.
Posted on: 2/7/2012 6:21 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10947866

RE: New Bright Nitro Skidoo MXZ Snowmobile
Yes, that guy (Mr. Krupp) builds great models. He's also been trying to get a manufacturer to accept and build his designs for a few years now. Don't know why he has no takers. Many people would love one of his snowmobiles even if it cost $900.00.
Posted on: 2/7/2012 6:14 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10947854

RE: New Bright Nitro Skidoo MXZ Snowmobile
She's moving pretty good - Awesome - I love RC snowmobiles! We've had very little snow here as well. One freak storm just before Holloween and another in mid January which melted away in 2.5 days. Philadelphia, PA
Posted on: 2/6/2012 10:12 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10946480

RE: New Bright Nitro Skidoo MXZ Snowmobile
FYI Hurricane Fibers has put up a new post of some of his works in progress including a new Nitro sled. http://www.rcuniverse.com/forum/m_10942972/anchors_10942972/mpage_1/key_/anchor/tm.htm#10942972
Posted on: 2/6/2012 6:31 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10946209

RE: nitro mod mxz newbright snowmobile
Hi Hurricane Nice work - can't wait to see them in action. Nitro may not be as fast but I think the realistic sound will put a smile on your face for sure. P.S I'm really interrested in how your replaced that hex main drive axle with something else. Mostly I'd like to see how you attached the spur gear and the lugged drive wheel to the new shaft (round shaft - you and I have spoke about this and is one area I'd like to fix on my own sled?). Both MXZ and Rev XP models use this hex axle. Could you give us some pics of this?
Posted on: 2/6/2012 6:18 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10946197

RE: New Bright Nitro Skidoo MXZ Snowmobile
[b]sumrcruz[/b] Maybe your handle should have been "wintrcruz" ! Do you have any video of her running in the snow? Maybe next season I'll add those front turn buckle mods to my sled.
Posted on: 2/3/2012 6:11 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10941607

RE: New Bright Nitro Skidoo MXZ Snowmobile
[b]sumrcruz[/b] Maybe your handle should have been "wintrcruz" ! Do you have any video of her running in the snow? Maybe next season I'll add those front turn buckle mods to my sled.
Posted on: 2/3/2012 6:10 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10941604

RE: Skidoo Rev XP snowmobile hop-up
That's the million dollar question. You'll just have to experiment to see what works the best.
Posted on: 2/1/2012 4:02 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10939124

RE: New Bright Nitro Skidoo MXZ Snowmobile
[b]sumrcruz[/b] Awesome job man! Quite the little club we have going on here. I love the belt drive system. Would you mind sharing more info on the parts you used for that? You also did a great job on those upper and lower links.
Posted on: 2/1/2012 3:53 PM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10939111

RE: Skidoo Rev XP snowmobile hop-up
All right - now that's what I'm talking about - very slick. It's starting to take shape - nice work!
Posted on: 2/1/2012 12:16 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10938790

RE: New Bright Nitro Skidoo MXZ Snowmobile
You need to fix your suspension as outlined on page 1 if you are still using the stock suspension. This will remove most of your issues such as track slip and binding. I run my snowmobile mostly on flat snow (which we have little of) so I can't say I have experienced the binding you described.
Posted on: 2/1/2012 5:24 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10938165

RE: Skidoo Rev XP snowmobile hop-up
Yes, 380 is too small. I used a 480 brushless (26mm) 400watt 2300kv motor (If I did this over I'd try to get a 3000kv motor). The 540 will definitely be better and give you way more power and speed. It will also require you to build a custom drive train and motor mount. If you go this route, I'd go with a 3000-3300kv brushless motor.
Posted on: 1/31/2012 5:45 AM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10936561

RE: New Bright Nitro Skidoo MXZ Snowmobile
Sure it's easy Don't use the "Fast Reply" option at the bottom of the post page. Use the "Post Reply" button at the bottom left of the screen. This post screen has an option link at the buttom "Click here to upload images and files". Then just use the "Select a file to upload" screen to select the images from your computers hard drive. You can add up to 12 pictures at once.
Posted on: 1/30/2012 6:09 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10934831

RE: New Bright Nitro Skidoo MXZ Snowmobile
Here are some pics of the following: 1) New aluminum tunnel cover 2) Tunnel cover installed from top and buttom views 3) New tunnel cover with the heavy metal motor floor board installed 4) Picture of how I used some threaded rod to attach the shocks to the chasis
Posted on: 1/28/2012 6:55 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10932028

RE: New Bright Nitro Skidoo MXZ Snowmobile
Oh, and that clutch bell is 14 tooth 32 pitch.
Posted on: 1/27/2012 3:00 PM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10931153

RE: New Bright Nitro Skidoo MXZ Snowmobile
alexjschauer Unfortunately, this is the engineering process. You try something and when it fails, you go back and make it better. I am currenlty performing the "exact" mods you described above. My black plastic cover also cracked, and yes, I too re-enforced it with fiberglass as well as sheet metal on top. I used a sheet of hobby shop bought aluminum and it fit the space perfectly. I bent the metel over my table top in a few places and viola! new cover in about 1/2 hour (not including drilling all the holes to mount it). I don't have time right now to post the pics I took just a few days ago of my double sheet metal motor mount but I'll post them tomorrow sometime. Your going to need to build a better drive train to hold the gears in place. For the hex drive shaft, I drilled a small hole in the platic body in order to slide it out without bending it. I hated to do that but it seemed was the only way to remove it. To see your subscribed forums, click the forum drop down at the top of the page. Select "My Forums" and scroll all the way down to the bottom of the page where they will be listed.
Posted on: 1/27/2012 2:58 PM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10931149

RE: New Bright Nitro Skidoo MXZ Snowmobile
[b]alexjschauer [/b] I read the rest of your thread. You did a great job on your MXZ build. What I like about you is that you didn't let others dissuade you from building your sled. A lot of people talk but you are a doer and made your snowmobile instead of asking others to do it for you. For that, I congratulate you. P.S - I am also an engineer. Now onto your issues. [b]Slipping[/b] 1) Your slipping is probably coming from the track slipping on the main drive wheels. You need to remove the drive wheels and flip them around so that there is more of the plastic lugs making contact to the track (not sure why New Bright didn't do this to begin with). You'll need to cut one of the plastic axles down some for this. I have a picture on my other XP build thread located at this URL on page 4. I'll also try to get some better pictures of this later today for you: http://www.rcuniverse.com/forum/m_9458566/mpage_4/key_/tm.htm [b]Suspension[/b] 2) Instead of building a whole new suspension, try strengthening the stock one. What I did was fill the plastic suspension bars with fiber glass and resin (Sig fiber glass kit) or you can fill them with Epoxy. One other thing you can do is to cut some metal rod insert some metal rod into the suspension bar slots and fiber glass/epoxy them in place. This works pretty well and will save you tons of time - now that it's winter and snow is here. Wait until summer to build a new suspension if you really want to go that route. [b]Shocks[/b] 3) For shocks, I pretty much used standard, cheap oil filled car shocks and they fit very well. Get the threaded ones where you can adjust the ride height with the thumb screw and set them to a lower setting (softer). [b]Clutch[/b] 4) I'll need to get back to you on the clutch bell. Basically, I tried to get one of the smallest clutch bells I could so I had more low end power.
Posted on: 1/27/2012 6:11 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10930335

RE: New Bright Nitro Skidoo MXZ Snowmobile
Hi alexjschauer Looks like you have all the right parts. Tell me what problems you are having and I'll try to help you?
Posted on: 1/26/2012 5:45 AM by Author "TechyJoe" in the forum "Toy-Grade RC Products"
http://www.rcuniverse.com/forum/fb.asp?m=10928471

RE: Skidoo Rev XP snowmobile hop-up
Sokey70 Here's what I did for the Rev XP. This stopped all slipping: This picture only shows 4 metal tabs on the main drive wheel but I added all eight tabs to make it work really good.
Posted on: 1/22/2012 2:24 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10921875

RE: Skidoo Rev XP snowmobile hop-up
Sokey70 To reduce the track slipping on the MXZ, you need to flip around the main drive wheels. You'll need to cut some of the axle off one of the drive wheels to make this work. See the pictures below:
Posted on: 1/22/2012 12:34 PM by Author "TechyJoe" in the forum "Unusual R/C"
http://www.rcuniverse.com/forum/fb.asp?m=10921699