Miller Electric

Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums

The forum is currently undergoing maintenance and is in a 'read-only' mode for the time being. Sorry for the inconvenience.


  • If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Announcement

Announcement Module
Collapse
No announcement yet.

Material recommendation for a motorcycle based trike????

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Material recommendation for a motorcycle based trike????

    Hi i want to get some ideas for material to build a light weight but strong trike frame, i was looking at either mild steel or aluminium but as i donít know much about chassis construction im asking you guys for some help,

    The engine for the planned trike is a Honda vf750 producing around 120bhp, i would prefer to use some sort of aircraft grade steel but not sure what to go for????/

    Please help

  • #2
    Material

    Hi I build custom Barstool Racers and have used both Alum. and steel tubing, both work well you just have to make sure you use proper gussets to make you're frame strong.

    Comment


    • #3
      Depending on total weight. I am using 1 1/4 HREW for most frame components and 1.5 DOM for overhead and roll components. I use .060 to .100 wall thickness depending on location and strength required. Might have a look at the Barracuda plans for an idea. Look also at Off Road Fab Network and see what those guys are using in their weekend wheelers and off road buggies. Too broad of a question without clear plan of what you want to build and what you plan to do with it really.
      Bob

      Comment


      • #4
        Don't want to rain on your parade, but with the knowledge base you have shown thus far you may be better off taking baby steps with this project. Bar stool racers, excellent start, short chassis, low flex...off-road vehicles, more education, lot more flex and engineering...highway operation, forget it for now. I'm not trying to put you down, but you're asking a mighty basic question for a guy attempting to fabricate a vehicle with 120bhp. If it isn't for highway operation, have at it, its your hide.

        I got to see my brother lose the front end of his Corvair trike back in our high school days coming by the Dairy Queen @ 10-15 mph after he had driven it over from the next town. He got lucky...only a bad case of road rash and wounded pride. Worked well for a year or so, but a molded in steering hub with a nice paint job didn't hold up with bad engineering and suspect welds...18" over Harley springer and too many wheelies were just too much.

        Comment


        • #5
          Originally posted by WyoRoy View Post
          Don't want to rain on your parade, but with the knowledge base you have shown thus far you may be better off taking baby steps with this project. Bar stool racers, excellent start, short chassis, low flex...off-road vehicles, more education, lot more flex and engineering...highway operation, forget it for now. I'm not trying to put you down, but you're asking a mighty basic question for a guy attempting to fabricate a vehicle with 120bhp. If it isn't for highway operation, have at it, its your hide.

          I got to see my brother lose the front end of his Corvair trike back in our high school days coming by the Dairy Queen @ 10-15 mph after he had driven it over from the next town. He got lucky...only a bad case of road rash and wounded pride. Worked well for a year or so, but a molded in steering hub with a nice paint job didn't hold up with bad engineering and suspect welds...18" over Harley springer and too many wheelies were just too much.
          They are wise words indeed.

          We call it CDS tube seamless you call it DOM which would be a great place to start Also make joints and perform destructive tests to determine how well you are going. The main rule with tube joints in NO GAPS. The better the fit the better the finish.

          Comment


          • #6
            Originally posted by WyoRoy View Post
            Don't want to rain on your parade, but with the knowledge base you have shown thus far you may be better off taking baby steps with this project. Bar stool racers, excellent start, short chassis, low flex...off-road vehicles, more education, lot more flex and engineering...highway operation, forget it for now. I'm not trying to put you down, but you're asking a mighty basic question for a guy attempting to fabricate a vehicle with 120bhp. If it isn't for highway operation, have at it, its your hide.

            I got to see my brother lose the front end of his Corvair trike back in our high school days coming by the Dairy Queen @ 10-15 mph after he had driven it over from the next town. He got lucky...only a bad case of road rash and wounded pride. Worked well for a year or so, but a molded in steering hub with a nice paint job didn't hold up with bad engineering and suspect welds...18" over Harley springer and too many wheelies were just too much.
            not trying to sound a bit a bit pissed off but i may have worded my thread wrong, but i have use 32mm dia cfs 2.4mm in the passed to build trike i was just trying to get ideas on different types of metal like t45 or some sort of alumunium but not using alumunium alot in this sort of way i was after some ADVISE not slagging off

            Comment


            • #7
              Originally posted by grommet View Post
              not trying to sound a bit a bit pissed off but i may have worded my thread wrong, but i have use 32mm dia cfs 2.4mm in the passed to build trike i was just trying to get ideas on different types of metal like t45 or some sort of alumunium but not using alumunium alot in this sort of way i was after some ADVISE not slagging off
              I'm gonna take a guess and say that yer not from these parts...are you?
              Reason I say that is I might have a bit of interest in your question but I don't have the foggiest idea of what size you are talking about. And I also never heard of the metal you mention either.
              I am guessing that if your were to convert all that data over to something more American, or something at least a hillbilly like me can understand, you may get some decent feedback.

              Comment


              • #8
                ok sorry cd cfs seemless is the same as your dom tubing, basically cfs mechanical is what we use in the UK to make roll cages, T45 is a very high carbon grade mild steel used on aircraft, but what i was tring to find out is i know you lot use chromolly seemless, but i wanted some advise on different metal like aluminium and if that can be used to build a small trike frame and long with the wishbone suspension that i want to make......

                Comment


                • #9
                  Originally posted by grommet View Post
                  ok sorry cd cfs seemless is the same as your dom tubing, basically cfs mechanical is what we use in the UK to make roll cages, T45 is a very high carbon grade mild steel used on aircraft, but what i was tring to find out is i know you lot use chromolly seemless, but i wanted some advise on different metal like aluminium and if that can be used to build a small trike frame and long with the wishbone suspension that i want to make......
                  If you wanna use aluminum for this you better go to school and get your engineering degree first....and I am NOT kidding you one bit.
                  I will begin with this (and you probably don't want to hear it), if you have to ask this question then you don't have any business trying to do this. Their are people whom you could pay to do it and it would be fine, but at the stage of the game you are at it could get you maimed for life and anyone else involved as well.

                  Aluminum should not be flexed over and over like steel. Think of a soda can tab. That is your frame. Where ever a thick part meets a thin section is where it's gonna crack.
                  The flexing is known as cycling and even a vibration counts. So if you had a big engine that vibrated a lot, you would have MILLIONS of cycles besides all the road cycles you would encounter going down the highway.

                  Next if you did have it designed by an engineer, and you made it out of the proper alloy, it would have to be heat treated after it was built. Aluminum completely looses it's temper in the weld area.
                  You could make it out of one giant chunk of aluminum by machining it and be plenty strong, if you had a good enuff design. There sure would be a lot of wasted material on the floor tho.
                  If you still insist on an aluminum framed trike, then find a motorcycle with one and make a swingarm, but leave the original frame alone. Even then it would be stupid simply because the twisting forces on a trike are present that the motorcycle would never see.
                  So MY answer is NO you should not do this. I work with aluminum everyday and I own an aluminum welding biz. That is 99% of my income. If I were to build a trike I wouldn't even consider using aluminum for the frame.
                  This would not be that much different than an airplane frame made from aluminum...it must be an absolutely perfect design and be properly heat treated besides having periodic inspections that would possibly uncover defects that would render it as useless.

                  Comment


                  • #10
                    Why not a rigid frame aluminum trike? Build the frame skookum enough that it doesn't flex and I don't see a problem with it. If ALU is strong enough for fuel trucks to haul 40,000 litres of fuel (that's about 10,500 gals. for you americans) down the hiway or to make 900 lb snowmobiles climb straight up mountains I don't see why it wouldn't work to build a weekend cruiser.

                    I say find some engineering info on different grades of ALU such as weight loading and cycle limits and go to it.

                    Comment


                    • #11
                      Fusionking maybe you could learn the metric system?

                      T45 is AWESOME material has excellent properties, like Fusionking says though Aluminium is a bit different it does not have the inherent strength of steel. Typicaly a aluminium section of a motorcycle frame will be roughly twice as thick as a steel section. Aluminium will distort a lot during welding and you will have to weld it on the jig and be mindful of your cooling rates.

                      I seriously suggest you buy John Bradley's book 'The Racing Motorcycle Vol 2 , A technical Guide for Constructors' John is a highly respected engineer(and lecturer) and is always willing to give his advice .

                      Comment


                      • #12
                        thanks 2T Institute i will have a look at this book as for some of the others on this thread you know jack about my welding skills, i have well over 32 current codings inc alu, stainless etc, so thanks to anyone thats wants to give a little advise but to anyone that wants to put me down go and f$*@ off

                        Comment


                        • #13
                          Hi Grommet,
                          Most steel based motorcycle frames are made from chrome moly with similar properties to 4130.
                          Old BSA frames were made from Reynolds 531.
                          The modern ali frames are highly engineered. They are made up of cast ali sections that are welded together.
                          Ali does suffer from fatigue and will fail via cracking.
                          Ali also has strength loss in the HAZ of all welded joints. Post welding heat treatment can solve this.
                          Before the modern ali framed MX bikes a few accessory companies made some ali swingarms. These were heavier than the steel ones due to the depth of section and wall thickness needing to be twice that of steel.
                          In 1964 BSA made 40 titanium frames for their world cup mx bike. these cost a fortune and were not designed very well.
                          You could try Ti if you can afford it.

                          Ji

                          Comment

                          Working...
                          X
                          Special Offers: See the latest Miller deals and promotions.