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Post by TomyJ on Nov 24, 2018 12:42:10 GMT -5
Need to bend the upper frame rails out (left and right) so I'll have at least 16" on the inside, the engine is 15" wide, and again fittings of jack shaft and gear shift, exhaust mounting, so many things to consider???
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Post by TomyJ on Nov 25, 2018 22:50:30 GMT -5
Time to do some mock up on the jack shaft diameter or how many teeth per diameter? Or remember that big pot hole that almost bottomed out the car, I think a 4" would ease my mind now to figure the teeth for a 530 chain (Harley) 2.75 dia. sprocket = 16T, so I am GUESSING about 25T and I'll try to use the same size engine sprocket. Edit, There is a site for sprocket diameter to the number of teeth, 530 chain, 20T = 4" and 15T = 3" this will really help out for my jack shaft...
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Post by TomyJ on Nov 28, 2018 19:16:06 GMT -5
Yeaaa! eBay's snail mail is here, one day late, Harley sprocket 46T and flat head bolts for recessing to get a little closer to the swing arm side. Dropped off at the machine shop for countersinking, This is why I bought a painted sprocket, did not want to cut up the chrome, so I'll just paint it the trike color RED, should be finished tomorrow then set up the wheel to swing arm and then back to the upper frame rails...
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Post by isaiahcrem on Nov 29, 2018 9:25:00 GMT -5
Looking good TomyJ!
Have you figured out how you plan to use the bellcranks yet?
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Post by TomyJ on Nov 29, 2018 12:09:19 GMT -5
Hi Isaiah, First I want to align the wheel and swing arm, dial in the upper frame rails for the control arms, THEN see what I can do with the bell cranks and coil overs, which would mean "IT'S ROLLING" Yeaaa! (soon). Working with push rods front and rear for adjustability will be nice, any tips on setting them up??? Yours is looking pretty good by the way, that trailer thing put the scares to me though I'm glad you made it ok. Be cool and have fun...
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Post by isaiahcrem on Nov 30, 2018 13:37:43 GMT -5
Hi Isaiah, First I want to align the wheel and swing arm, dial in the upper frame rails for the control arms, THEN see what I can do with the bell cranks and coil overs, which would mean "IT'S ROLLING" Yeaaa! (soon). Working with push rods front and rear for adjustability will be nice, any tips on setting them up??? Yours is looking pretty good by the way, that trailer thing put the scares to me though I'm glad you made it ok. Be cool and have fun... When setting them up it will be good to avoid the need for thrust bearings. The needle bearings in the bellcranks are only meant for loads perpendicular to the length of to the pivot bolt. Or loads that make the bellcrank turn around the pivot. If you look in my photo below, you'll see that I have a large washer holding the bellcrank downward (Or towards the rubber body panel below it). This is because of the angle of my pushrods. They not only put force around the pivot, but they also put a force along the length of the bolt. Currently, the large washer in my photo is rubbing the top of my bellcranks and acting as my short term thrust washer/bearing. In all reality I should have a thrust washer/bearing on it but wanted to wait until I dialed in what ratio I wanted for the bellcrank, then fabricate my own with the bearings in consideration. Let me know if that makes sense. I'm not the best at typing out what goes on inside this engineer's head. Thanks for the compliment! The trailer was definitely a nervous moment, but it stayed put the entire 2-hour drive with multiple railroad crossings. I used extra ratchet straps because I've never hauled something that doesn't fit into a trailer Hopefully I can get mine stripped down for paint before christmas, but I won't know until i'm moved into my dad's and get this new job started. Keep up the good progress, I'm enjoying watching the build! Isaiah
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Post by TomyJ on Dec 1, 2018 19:53:28 GMT -5
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Post by TomyJ on Dec 4, 2018 22:24:06 GMT -5
Now for a little color...
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Post by TomyJ on Dec 8, 2018 18:40:58 GMT -5
The color, I want a medium red shade that can be seen from a distance. Working on the paint for the swing arm now, and yes I remember the caliper bracket weld on, but later. I have to rely on rattle can for now...
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Post by TomyJ on Dec 13, 2018 19:53:21 GMT -5
Hmmmmm!!! Maybe orange? Do you think a red chain might be too much? heeheehee Tomorrow is off to the machine shop for more little pieces of the frame to swing arm and the changing of the rear frame width rails.
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Post by TomyJ on Dec 15, 2018 19:29:51 GMT -5
Rear brackets, shock brackets, and wheel spacers finished machine, how much travel do I need for this coil over??? I can get to 1/4" closer to the frame rail...
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Post by TomyJ on Dec 16, 2018 19:05:33 GMT -5
Wheel spacers are machined, painted and installed. More mock up with the coil over location, Just not happy with it still...
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Post by liteway on Dec 16, 2018 19:37:39 GMT -5
Hello Tomy.
In the last photo you are giving us an upside down view, No?
I say this as it appears any upward motion in the rear wheel ( as things are oriented in the photo) would pull on the coilover , not compress it.
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Post by TomyJ on Dec 17, 2018 13:55:36 GMT -5
Hi Liteway Thank you for your input, I have never claimed to have a engineering degree BUT I wish to, to many do overs. With the swing arm in this position I can achieve the low seats I want BUT there must be a pushrod to the coil over? (yes) My biggest problem to this is the length of a rocker arm (say 6") might do it? And yes I can use any help that will slow down the do-overs. Such as how much will the shock sag at the rocker arm? In the last photo I put a 1/8 shim under the shock and this is why I made the comment of not being happy the mockup??? OK, OK, BACK TO THE DRAWING BOARD...
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Post by liteway on Dec 17, 2018 14:42:29 GMT -5
I too suffer from a lack of engineering skill, so I can sympathise.
Use of a pull rod below the front swingarm pivot, as you have envisioned, is a way to save space and keep weight low.
It can be done close to what you have there by swapping the connection points of the pull rod and center pivot. That is,place the rocker pivot opposite the coilover and connect the pull rod someplace in between the two.
Make a test rocker with holes drilled across its length that will allow to test the effect on suspension travel and stiffness when attaching the pull rod and rocker pivot at various spots along the rockers length.
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Post by TomyJ on Dec 17, 2018 21:02:35 GMT -5
Liteway thank you again, I hope this one will work? Dave, did you notice the wood? I did not want Admin to feel bad about his 2x4 special,
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Post by liteway on Dec 18, 2018 1:23:14 GMT -5
lookin good.
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Post by TomyJ on Dec 18, 2018 20:52:48 GMT -5
Another view...
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Post by TomyJ on Dec 20, 2018 21:16:26 GMT -5
Getting closer, the rework is killing me...
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Post by TomyJ on Dec 21, 2018 20:17:35 GMT -5
This is going to take awhile, I know the brace has to be very strong and maximum movement. These plates are 1/4 thick and so will be the brace, maybe a rocker style bolt down for the shock top?
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Post by joesarasota on Dec 22, 2018 9:48:35 GMT -5
If I may suggest from an engineering standpoint the pivot point of that suspension has a high shear load. An alternative design that would transfer the load more evenly with less moving stress points is as follows: From the rear wheel pivot arm mount a moving rod that passes between two horizontal shocks that are mounted closest to the rear wheel. The other end of that moving rod connects to a moving bracket that is mounted to the opposite end of both shocks. As the rear wheel moves up the center rod is being pulled along with the dual shock bracket compressing both shocks. I hate redo's but it's a lot easier at this point, either way, best of luck!
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ahweh
New Member
Posts: 48
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Post by ahweh on Dec 22, 2018 19:11:33 GMT -5
I drew up a couple possible changes for you to consider. I hope you can see what I am trying to convey to you. flic.kr/s/aHskKZfAWR
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Post by TomyJ on Dec 22, 2018 20:16:56 GMT -5
M Flipped over the swing arm and added the front coil overs??? I really want the red coil overs for the front and the yellow single coil over is giving me to much height...
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ahweh
New Member
Posts: 48
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Post by ahweh on Dec 22, 2018 23:02:14 GMT -5
I belive it is possible for you to get closer to what you are after by trying different things which is what I think you are doing.
since you want to use just one shock absorber in the back you might try the demonstration-2 picture that is a part of the link posted.
it might get you at least one step closer to what you are looking for.
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Post by davej98002 on Dec 23, 2018 0:30:58 GMT -5
Too bad there is a much lighter spring for that shock. That way you could mount it and see how it works.
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Post by joesarasota on Dec 23, 2018 12:08:26 GMT -5
Pictures 1 & 2 are good illustrations if your preference is the single shock, a couple of modifications for strength & kinematics might be as follows: Create enough offset so the shock mounts in a different horizontal plain than the push rod, for instance create the fixed mounting point square tubing bar welded to both sides of the frame rails for superior strength. Then slightly above or below the shock have the push rod return to the pivot point. Consider the bolt or pin for the pivot point a 1/2" or larger like a hardened shoulder bolt. The double pivot arm (top & bottom) is also a good consideration, however for initial test purposes you could make a single with multiple mounting holes to identify the ideal rear suspension characteristics, good luck!
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Post by TomyJ on Dec 23, 2018 19:12:10 GMT -5
Thank you guy's for your help and encouragement, this next mock up I feel is to high with the weight but it is compact and simple. I flipped the swing arm back to the down side because of low weight and I wanted the weight of the shock supported close to it's self and the frame... Again please give me your input is there something I am not seeing???
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Post by joesarasota on Dec 23, 2018 21:23:56 GMT -5
Yes, try not to offset the shock & pull rod, instead consider mounting them centered one over the other. Using your last picture, you could have the pivot arm 90 degrees from where you're showing it so that it's vertical.
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Post by liteway on Dec 23, 2018 22:03:51 GMT -5
The basic geometry looks ok but its unlikely to work well without a lot of fiddling with angles, coilover mounting points, rocker length , link mounting points, etc. For instance, it may ultimately prove better to swap the relative positions of the coilover and swingarm link to achieve the desired combination of travel and stiffness. It would take a better man than me to tell you how to get the details right first rattle out of the box. I'm a trial and error man. It would be impossible for me to work out a final solution without first loading the rear wheel with the weight of the finished trike and rider and giving everything a good bounce with each mod.
Hopefully somebody here can provide you with a clearer path forward than that.
Knowing my limitations, I opted for a linkless monoshock between the frame at the back of the motor and above the swingarm pivot, like many production bikes. See Kawasaki Versys. Its light and simple with less variables to sort, mainly shock angle and anchoring points. And its out where you can experiment with it and do your welding after much of the construction is done.
Have you considered how high your engine will have be mounted, especially if using the under motor exhaust of most bikes?
Having said all that, its a lot of fun, satisfying and a good challenge in creating stuff that's new, different and functional.
Just remember the road less traveled can be strewn with big rocks and rattlesnakes.
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Post by davej98002 on Dec 23, 2018 22:45:06 GMT -5
Another link system would be to copy one of the scooters out there like a Burgman 400 or Yamaha T-Max. It uses a Mono shock and a link.
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