Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Modification info Victoria

Discussion in 'Modifications and Projects' started by DTyamy, Nov 20, 2009.

  1. I am starting a little cafe racer project and am not sure of the modification laws in Victoria. Can you use an engine in a different frame by the same manufacturer. ie, Yamaha DT 175 engine in a Yamaha TT350 frame.
    Also can you use a different front and rear end, ie Honda NSR 250.
    I would appreciate some info on what is or isnt allowed.
    Tried reading Vicroads info but I'm not very good with gobledegook.

  2. The motorcycle frame is usually what is registered. Swapping in a similar size engine (regardless of brand) is usually okay but if the frame is modified (welded) you will normally need an engineers certificate to get rego. Swapping other front ends, swingarms etc. that is a virtual bolt up is usually not a problem, especially where it improves braking etc., the issue again is when the frame is modified to make it fit. You can pretty much do anything to anything however, provided an engineer will sign it off.

    Obviously avoid going backwards (drum brakes on a gixxer engined bike for example!). Though I am at a loss as to why you would want to put a DT175 engine in a TT350 frame! The early XT/TT and similar 4 stroke road trails lend themselves well to all kinds of projects, I am actually on the lookout for a cosmetically poor XT550 for a similar project I have planned! (just in case you know of one!)
  3. Hi, thanks for the info, does an engineer have to sign all the mods off before registration? I used one when building my open wheeler Clubman, I'll have a word with him.
    I am not actualy putting the DT175 in the 350 frame I was just using it as an example, at least I dont think so. The DT175 frame is to small for me and I need something to cary a little more weight and height. I have collected most of the parts whilst having the casings blasted and powder coated. The top end has also been polished and flowed, new bearings, rings, etc. I want a little lightwieght 2 stroke bike that is why trials or motorcross bike frames look good.
    I have the front end complete from an NSR 250 with magnesium wheel and rear end with a box section swing arm and matching wheel.
    Which frame to use is my last choice, even the honda, yamaha 250 road frames are heavy compared to xr250 or xl250.
    Will post some pics as it grows.
  4. Maybe something like an IT175 or IT250 frame? Motor should just about bolt in and should be taller lighter and stronger than the DT frame? Also has compliance which is essential to get rego (otherwise you could use a YZ frame!) The DT200 has a bigger frame than the 175 and may also work. I have a DT200 (my dirt/road runaraound!) and also an old scrappy DT175 frame here if you want any pics, measurements or comparison.
  5. Hi, Yeh I have just tried the NSR250 front and rear end in a borrowed WR Yamaha frame, The rear goes fine but the front end is a problem. The WR headstock is about 50mm to long. The forks on the NSR are an odd size as well 39mm and to short by about 75mm for this setup. I am going to have to get a longer stem in the triple clamp and longer forks, I think some harley tubes are 39mm. If I push the clamps down the forks I am left with less than100mm travel and I dont think thats enough.
    The other way and easier I think, is to use the wheels brakes discs etc off the NSR and the triple clamps and forks the same dia off a WR. I tried the 4.5 rear wheel into the WR swing arm and it fitted a treat.
    Other than that I think it's back to looking at road frames. I prefer a tubular frame as it gives a more retro look.
    Is the old DT175 frame you have, a pre 1974 with the single post at the rear or later double frame all round.
    If it's the later frame I would be interested in the headstock length and the width of the frame at the swingarm pivot.
  6. Hey All,

    I plan on buying a Virago in the near future and was wondering what the laws are concerning subframe modification/removal in Victoria. Could someone clarify? I've been searching around but can't find anything on it.

  7. Strictly speaking I think you need a engineering report. The following link may help: Infrastructure Vehicle Regs LL Motorcycles and 3 wheel.
    • Like Like x 1
    • Funny Funny x 1