Rock Solid Engines Billet Inlet Tube

Discussion in 'Spare Parts, Tools & Product Developement' started by AussieSteve, Dec 24, 2009.

  1. AussieSteve

    AussieSteve Active Member

    Mentioned this in another thread, Rock Solid Engines laser-cut inlet gasket, so some of this is repeated.

    Bought a Rock Solid Engines billet aluminium inlet tube with 'O' ring the other day, $35AU + delivery, for HT 2-stroke engines.
    Not too impressed. Beautifully machined, looks great, but only 1½" long and straight, so the carb interferes with the clutch cable and is on a 25-30º angle. Also, the 'O' ring isn't quite close enough to the end of the tube to guarantee a good seal with the slots in the carb.
    On top of this, the inlet is machined for allen-head screws, so the stock studs must be removed and allen-head screws found.
    Score: 3/10 (Would have been 2/10, but it is a good little paperweight and the 'O' ring was useful on my filed alloy inlet.)


    Better to save the $$$ and file a groove in a ($10US) after-market alloy tube to fit a (30c) 'O' ring.
    See: NT carby/inlet leaks - a reliable solution


    Late edit: After the above pic was taken, I filed more off the end of the tube so that the 'O' ring is only about 1mm from the end.
    Also, smooth the ragged edges of the slots in the carb opening before fitting or the 'O' ring might be nicked resulting in a poor seal.
    On top of this, a bit of 2-stroke oil on the seal when fitting the carb is a good idea.
    And finally, ensure that the 'O' ring is fuel resistant or it will swell out of control on contact with fuel. (Been there, done that, years ago)

    ... Steve
    Last edited: Dec 24, 2009

  2. super dave

    super dave Member

  3. give me vtec

    give me vtec Active Member

    thanks for the info... I was seriously debating with myself on buying one of these things.
  4. super dave

    super dave Member

    well Aussie is rite just remember you do have to do some other work to fit it, if you have to time this is what it is all about not just bolting on parts but working on your bike. this forum has been a great source for helpful info.
  5. AussieSteve

    AussieSteve Active Member

    I could have moved the cable adjuster, but my carb was on too much of an angle for my liking.
    Either method requires a bit of work. I like the modified alloy type, but the short one would help in frames that are a tight squeeze.
    For flow, a stock steel tube is probably best, but they're not thick enough to cut an 'o' ring groove.

    ... Steve
  6. danlandberg

    danlandberg Member

    :confused:Just going through threads, and I bought one of these. Do you have pics of the clutc tube mod?
  7. danlandberg

    danlandberg Member

    If I have a problem with this fit where can I get a clutch roller set up? ( I has seen them her before but can't remember where) I am borrowing a neighbors puter so I'll get mine up & going tomorrow!
  8. AussieSteve

    AussieSteve Active Member

    I never did fit my billet inlet, Dan, so I didn't change the clutch adjuster position. It's sitting in the shed, unused.
    As you can see in the pics of my bike on my profile page, or even my avatar above, my engine leans forward a lot, so the billet inlet wasn't suitable. The carb was tilted too much for my liking.

    I just checked out the pics of your bike, your engine isn't tilted much, so you shouldn't have the problem that I did.

    Regarding the 'clutch tube mod', it's only a matter of removing the screw-in clutch cable adjuster from the top of the casing and cutting it shorter, then re-fitting it, so that the cable sits lower and clears the new lower carb position.
  9. AussieSteve

    AussieSteve Active Member

    Did you try searching 'clutch roller'?
    Al.Fisherman, (Ron Becker), sells them.
    If you scroll through the first few pages in 'Buy/Sell/Trade', you'll find the thread.
  10. danlandberg

    danlandberg Member

    Sorry Steve; But the pics of that bike was the one stold in Vegas. I liked that frame! But I got a D.I.Y. from B.B. and it does not go together as easy as you would think! The only mods on the Royce Union was front mount & tank spacers. I don't have the equipment to do what I need to do. (Motel life). I know I seen thing I'm looking for, To see if it might be useable or go in MY new unused box. LOL, Thanks for the reminder of where to look!!! Dan :whistling:
  11. AussieSteve

    AussieSteve Active Member

    Still, Dan, as long as your engine isn't tilted as much as mine, you'll have no trouble with the billet inlet. If you lived nearby, I'd give you mine to try. I'll never use it. I'll probably end up giving it to someone from MBc who needs it here in Oz.

    I didn't mean to be rude regarding searching.
    I just had a look and Ron's thread on the clutch roller is on page 3 of 'Buy/Sell/Trade'.

    Like you, I'm very limited with equipment. My build was done with no more than a hand drill, files and spanners. I was lucky that it went together so well, but it took 4 months and cost a total, now, of about $1600AU, ($1450US).
    Worth every cent, too. Effectively, it's a 66cc, 6-speed moped that needs no rego.
    An off-the-shelf, brand-new moped would have cost 2-4 times that.
  12. danlandberg

    danlandberg Member

    Sorry I did not mean to sound ignorant, maybe just to tired tonight to think of ordering any Moore parts at this time (been thinking to much planning on my next move). Have a good one Steve (sorry)
  13. AussieSteve

    AussieSteve Active Member

    No need to be sorry for anything - you've done nothing wrong and you don't sound ignorant to me.
    Just Pm'd you re the clutch roller. Ron does a good job on those - haven't heard a complaint yet.
    I know how you feel about ordering more parts - been there done that and it hurts, especially when a lot end up in that spares bin.
    Those BB kits should be a bit better than that, they need to supply suitable frames.
  14. danlandberg

    danlandberg Member

    That is the truth! I E-Mailed them about the problem I find in the D.I.Y. kits, and they mailed me back with the "need to have some mechanical knowledge" I guess I don't know what I'm doing after 28 years of mechanical experience, and 2 great builds. The only reason I ordered a kit like this, is because of my situation (room to work)
  15. AussieSteve

    AussieSteve Active Member

    Only 28 years, that's not enough for these things!
    Kidding - in reality, if they're selling an engine plus a bicycle to fit it to, it should fit.

    I'm a little luckier, I only rent a 2-bedroom unit but it has a brick, lock-up garage to work in.
  16. Fabian

    Fabian Well-Known Member

    Same here Steve - my billet Intake Tube does not allow the NT carburettor to clear the clutch cable post holder.
    Also the Carburettor sits on a fairly uneven angle of maybe 30 degrees.
    Not sure how it would affect the float in the float bowl.

    I used an alternative method of getting the NT carburettor to seal on the standard intake tube by placing an o-ring inside the carburettor and it seals up to the mating face on the intake tube.

    The billet intake tube is a lovely piece of work but it needs to be made as a curved design to clear the clutch post and have the carburettor sitting on a level plane.

  17. AussieSteve

    AussieSteve Active Member

    G'day Fabian.
    The clutch post isn't hard to change and the studs aren't hard to pull out for the allen head screws, but on my bike, the angle was all wrong.
    Many modern frames have a near-vertical seat tube. I chose to mount solidly there and adjust the front mount to suit. As a result, my engine tilts forward heaps, far too much for a straight inlet tube. With a shift kit, the engine must be aligned with the seat tube for a reliable setup.

    The 'O' ring method that you're using, although better than stock, is still not 100% reliable.
    You need to really push on the carb as you tighten the clamp to get a decent seal.

    If you have the time, it's worth filing a groove for an 'O' ring in an after-market alloy inlet.
    I'm sure you've seen my thread on the subject, NT carby/inlet leaks - a reliable solution

    I have 50 suitable 'O' rings here. (Wasn't worth buying less, but I'll never use them all.) All you need is the inlet and a narrow file. (I used a thin 'warding *******'.) Well worth the effort. No leaks here.
    If you want a few 'O' rings to suit, PM me and we'll work something out for posting them. Don't want payment - they're only 30c each, just an address to post to.
    (They're identical to the one on RSE's billet inlet. I bought them from 'Fitch Rubber' in Adelaide, one of Tony's neighbours. You can guess where he gets his.)

    Can't say b a s t a r d here, even if it's the correct term for a file.
  18. Fabian

    Fabian Well-Known Member

    I agree with you Steve (quote) The 'O' ring method that you're using, although better than stock, is still not 100% reliable.
    You need to really push on the carb as you tighten the clamp to get a decent seal.

    Yes, i do have to push the carburettor firmly up against the intake tube and then tighten up the clamping screw.
    Surprisingly, it's proven to seal reliably, so i haven't bothered to change methods.

  19. danlandberg

    danlandberg Member

    That is the same method I used & you do have to push hard enough to make it seal. I had no failure there, just manifold gasket(s) went through many till I :idea: made my own.
  20. danlandberg

    danlandberg Member

    Fabian: The mod is to cut a 1/4'' off the cable holder, But on mine the post is to tall also. I don't see a practical way to lower the post with out loosing #of threads and have the post hit the drive sprocket shaft.(at least on the Flying Horse engine). If you end up using the billet intake & get it to work/fit Please post pic(s) That is why I'm thinking of the roller set-up. :confused: