Reed valve with extended intake

Discussion in 'Performance Mods' started by jaguar, Nov 8, 2012.

  1. jaguar

    jaguar Well-Known Member

    Crazy test #1003: add a reed valve to a piston port engine with extended intake (7.5" total)
    Results: idled stronger with slightly better power taking off from a stop. 4% less top speed. no other power difference.

    Crazy test #1004: put holes in the piston skirt so that now it is an extended intake added to a reed valve setup
    Results: bad off idle power, 20% more top speed (+5.3mph)

    Crazy test #1005: remove extended intake
    Results: good power throughout rpm, gained .3mph top speed
    ReedExt.jpg
     

  2. jaguar

    jaguar Well-Known Member

    Also, if I had to choose between a reed valve and an extended intake for down low power, I would choose the extended intake. It has proven better in my tests.
    With the 60cc cylinder I am experimenting with I am very happy with how it runs w/o a reed valve or an expansion chamber. For most people it is as much as you need. I just like the fun of having extra mid range power with the torque pipe in place of the standard exhaust which is why I use it. But if I moved back to a hilly city I would probably prefer just using an extended intake. Probably the best mod there is for almost zero expense. In the picture above it is the sidestepping intake manifold from JNMotors that I used with a 2.5" length of automotive hose. It allows less carb movement than just using hose attached to the stock manifold.
    The 60cc cylinder is slightly ported. Most important is having increased the intake port duration to 120 degrees. See my page about upgrading from 48cc to 60cc for porting details.
     
  3. geebt48cc

    geebt48cc Member

    Jag, I notice that you've got pictured the RS reed with extention. So, do you think that this would work close to same with the Arrow reed staying at the 7.5 total length?
     
  4. jaguar

    jaguar Well-Known Member

    I would definitely try it.
    Try different lengths also. My 7.5" was without the distance of the reed valve. (The intake port is 1.1" long.)
    You should try it w/o the piston skirt "holed" and then put holes in it to see which way you like best.
     
  5. geebt48cc

    geebt48cc Member

    Well, I plan on doing that if the reed valve ever gets here?? Jag, I just really wonder if the Arrow reed will at least be as good as just using the extention has?.

    Hope that with using them both at a total length of 8.5", ..................

    (even though piston hasn't been ported for intake) it will hold its own.

    Uno, one would think for the 95.00 dollars, that there would be at least a small improvement............
     
    Last edited: Nov 9, 2012
  6. lazylightning@mail.r

    lazylightning@mail.r Active Member

    Hi Jaguar!

    I remember you writing once about the great synergetic effect of the pipe plus the reed valve and drilled piston. The test you made with the ported piston yielded lower torque now. Was that after changing to a 36 tooth rear sprocket?

    Would you say the plain ported piston setup with the pipe is better, than the pipe - plus reed valve and drilled piston? Or is the plain piston + reed valve and pipe better than just a plain piston plus pipe with no reed valve? I guess this means low end torque of course. And what about that super sweet middle to upper end where it wanted to do a wheelie? Then it may be a matter of choosing between the two? Low end or cruising power plus...
    I already have a 7.5 inch rubber hose extention from piston to venturi....due to frame - carb fitting problems =-)

    Best Regards,
    Paul
     
  7. jaguar

    jaguar Well-Known Member

    What I have written about here does not include use of an expansion chamber. Adding my torque pipe to any of these combinations will of course improve torque.
     
  8. lazylightning@mail.r

    lazylightning@mail.r Active Member

    So the pipe with the reed and drilled piston with boost ports is the best for low rpm torque from idle and for middle to upper power rush as well. Yes?
     
  9. jaguar

    jaguar Well-Known Member

    Yes but unless the engine is 100% optimized you can't expect any kind of rush. But the pipe in this context is my torque pipe, not the other pipes offered for sale.
     
  10. seb1008

    seb1008 New Member

    Would the weber carb work with the extended intake? I am going to buy the stage 3 kit from JNM and I was going to get the Arrow reed valve for it, unless you think the extended would work better.
    I am looking for low end power for using in the mountains on gravel roads. Elevation 300-3,000 meters but mostly in the 300 range. Towing a bike trailer. Motor is a 80/66cc with a jackshaft.
    Arrow Torquer 2 expansion exhaust.
     
  11. jaguar

    jaguar Well-Known Member

    It is all a matter of whether or not you can make it work with sizing. DIY if need be. But first ask JNM the same question.
     
  12. Fabian

    Fabian Well-Known Member

    Seems like we share similar setup goals. My solution was to incorporate a low and high range set of gears that are worked by a conventional front derailleur:

    http://motorizedbikeforum.the-talk.net/t384-mt-dandenong-fire-access-trail-september-2013

    http://motorizedbikeforum.the-talk.net/t380-lake-mountain-snow-adventure-august-2013

    give this page time for the photos to load

    http://motorizedbikeforum.the-talk.net/t393-multi-combination-bicycle-trailer-october-2013

    and give this page time for the photos to load

    http://motorizedbikeforum.the-talk.net/t341-walbro-style-carburettor-for-rock-solid-engines-reed-valve-intake
     
  13. lazylightning@mail.r

    lazylightning@mail.r Active Member

    If you need the bike to pull a trailer in the mountains and on gravel roads, I would recommend that you take the time to have someone make the Jaguar pipe for you. Otherwise your reed valve will yield no gain in torque at low speeds. The jackshaft is good because you shift gears and can get the torque this way, with application of higher rpms. One problem is that we are talking about off road stresses and real loads with a bicycle trailer going up mountain gravel roads. The bicycle chains may not hold up well no matter how carefully you shift. I'm using the stock 44 tooth rear gear instead of a jackshaft, but I am considering the 56 tooth gear for real mountain roads with my trailer, just because the speeds are quite slow at times with uneven rocky roads. Off roads and with a load are hell on these bikes.
    The Jaguar pipe has given me about 250%- 300% more power than just my ported cylinder with a bigger carb and milled head. Those things helped a little, but now with the pipe it's a monster.
    Here's some video of the trailer: http://www.youtube.com/watch?v=X0VR018hLNA and
    http://www.youtube.com/watch?v=LOC1rDO0Q18

    Here I took a ride to the custom bicycle garage where I work. For the first few minutes it's cold, but then later you can notice how it's more responsive http://www.youtube.com/watch?v=F3gAYQ6z1UE

    The trailer will hold about 350 - 400 kg (700 - 850 lbs) The question is whether I could ever pedal off from a stop with such a load. Definitely not on an uphill grade. I suspect that the maximum load will never be over 200 kg though, so all is well.

    ?????? 006.jpg ?????? 005.jpg ?????? 004.jpg 998053_10200503133844142_557573565_n.jpg SDC17340.jpg SDC17335.jpg SDC17336.jpg
     
  14. lazylightning@mail.r

    lazylightning@mail.r Active Member

    Wow Fabian! That's an amazing trailer caravan setup you have there! Do you use it on long road trips? Many people dont understand that the motorised bicycle can pull amazing loads as long as the weight is not sitting on the bike itself. The main thing is to get it moving with the pedals in first gear. I bet all the kids in the neighborhood make you give them rides. Do you use the setup in local parades or community type projects? It looks great and I'm sure you can haul lots of stuff in it! Those one wheel trailers are good too for the small trails. I'm hauling mining equipment on my trailer, thus it's rather heavy duty large parameters.
    Great job on the Walbro plus reed! Now you just need to get a Jaguar pipe on. ;-) I was looking around for one of those diaphram type carbs, but on my next super build with all the performance goodies I plan to aim for a motor that can achieve very high rpm's without sacrificing the low end power (Jaguar pipe plus high rpm pipe with a exhaust channel diversion switcher). So I need to get a carb with about 21mm plus in venturi diameter. I was loooking at the Walbro performance carb, but it seems to be about 13.5mm in venturi diameter. Do you know anything about this question? I'm still in the designing stages here.

    By the way, I read your post with the photos of the snow trip. That's great! I know what you mean about the engine and your heart working hard together. I love riding in the snow with my spiked tires. You gotta get the Jaguar pipe on man! Once I did, the snow is all mine! I fly off like a rocket across ice and snow with ease. And if I have to help with the pedals, then its only at extremely low speeds.
     
  15. Fabian

    Fabian Well-Known Member

    That's the reason why my bike is set up with a low range gearing operated by the front derailleur as shown here:

    http://motorizedbikeforum.the-talk.net/t132-tetra-chainwheel-system-for-sickbikeparts-sick-bike-parts-sbp-shift-kit






    That's what happens in the cul de sac every Christmas day when everyone gets together. The kids go bananas over it because when doing a U-turn, the last trailer is going backwards when the first trailer is going forwards, so the kids can wave to each other; going in different directions. The biggest problem i have is trying to keep adult women from wanting to ride in the trailers. Sometimes even grownups can't keep their inner 8 year old from bursting out.


    You will definitely need low range gearing (as depicted in the photos and video) if hauling mining equipment.


    Don't waste your time trying to get high rpm's out of the engine. You will experience significantly reduced engine life if going beyond 5,000 rpm. It's much better to get a reed valve intake and (if you can get away with it, a torque pipe) to give strong midrange torque in the 3,500 to 3,800 rpm range, and let the low range gearing do the work on the hills.


    Completely unnecessary if the engine operates under 5,000 rpm, and spends most of it's time in the 3,800 rpm range.


    I am trying to achieve the opposite by not attracting unnecessary attention to myself; having the bike operate as quietly as possible and reducing the rpm's as much as possible. The laws in my area are draconian against motorized bicycles, and the configuration of my bicycle as it stands will see me with $3,000 worth of fines and penalties if the police throw the book at me.
    My main goals are for the bike to be very quiet and to operate as stealthily as possible, yet being capable of tremendous pulling power for heavy haul situations.

    I don't take the trailer train out on the open road. If it is out on the road, it's only within my estate or it gets transported by car to the location where it will be used; typically being on bicycle trails to haul out firewood, which is inaccessible by a car and trailer.
     
    Last edited by a moderator: Dec 15, 2015
  16. seb1008

    seb1008 New Member

    Thank you Jaguar, I will check with JNM. I was going to try and order your expansion pipe, but the page said none were available so I went with arrows torque 2 because it was as close to resembling yours that I saw. I am pressed for time before I leave Florida and head for California. I wanted to thank you for all the information you post, I have a separate folder for your tips and one of Fabians that I am constantly rereading to get a better understanding of the dynamics of the bike builds.
     
  17. seb1008

    seb1008 New Member

    Fabian when I came across a post of yours a few weeks ago when I first got my bike I started for your posts because of how you set your bike up is how I want to set mine up.
    I will be using it on forest service roads in the mountains of north California where I prospect for gold. I am not looking for speed just pulling power. I have very bad rheumatoid arthritis that affects my mobility so I am trying to set this up as good as possible for reliability and simplicity of use.
    I have read everything I could find that you have written about the weber carb and reed valve. The only thing that has stopped me from ordering one is where I can buy or make the thermal plate. When I go to the rock solid web sight I get a page that says your country has been black listed.
    Could you tell me where to get this piece?
    If I cannot locate it my next choice will be the mikuni vm18, but I really like the ease of use that you talk about with the weber.
    Pablo at SBP said that the right hand chain tensioner should be available this week, they just have to be able to get it listed on there page. You recommend getting the left one also.l am just waiting for the right hand one to be listed before I place my order.
     
  18. seb1008

    seb1008 New Member

    Really nice trailer you have there lazylightning , I would use that behind my jeep.
    I wanted to get jaguars pipe but were not available so I went with Arrows Tourque 2 because it most closely resembled Jaguars pipe and I hope it will yield some of the benefits. I am pressed for time to get the bike ready before I leave for California to spend the spring, summer, and fall mining.
    What type of mining do you do and where about a do you mine?
     
  19. jaguar

    jaguar Well-Known Member

    yeah if you want a torque pipe now (my design) you have to make it yourself. I sold my old two experimental versions and thats the end of that production line. They are more complicated and time consuming to make so I doubt any distributor will ever have any produced, probably for fear of the final price. So you have to DIY. But the results are completely outstanding. Nothing comes close.

    about making a high RPM Grubee, well it can be done but the stock rings produce too much friction (which would rob power and wear down the cylinder plating) and the weak cylinder plating would be worn down by thinner rings (although they produce more power by having a smaller ring end gap) because they don't spread out the force. (the fatter rings spread out the spring and compression force from the rings to the cylinder). The only solution is spending $190 to replate the cylinder and then use a Minarelli piston and rings (1mm thick). But even with a torque pipe it would run like a dog at low RPM. Without replating I don't recommend going over 8000 RPM.
     
  20. Fabian

    Fabian Well-Known Member

    The right hand side chain tensioner is absolutely essential if you want the jackshaft system to be reliable in dirty, dusty, sandy or muddy conditions.
    The left hand side chain tensioner is not essential but (in reality) it increases the life of the jackshaft; adding strength to the system as well as reducing vibration.

    I consider both the left hand side chain tensioner and the right hand side chain tensioner to be essential items when ordering a shift kit.
     
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