www.recumbents.com
www.recumbents.com
www.recumbents.com
Home | Profile | Register | Active Topics | Members | Search | FAQ
 All Forums
 www.recumbents.com
 Technical / Bike Building
 Junior High Racer

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize:
UserName:
Password:
Format Mode:
Format: BoldItalicizedUnderlineStrikethrough Align LeftCenteredAlign Right Horizontal Rule Insert HyperlinkInsert EmailInsert Image Insert CodeInsert QuoteInsert List
Videos: Google videoYoutubeFlash movie Quicktime movieWindows Media videoReal Video
   
Message:

* HTML is OFF
* Forum Code is ON
Smilies
Smile [:)] Big Smile [:D] Cool [8D] Blush [:I]
Tongue [:P] Evil [):] Wink [;)] Clown [:o)]
Black Eye [B)] Eight Ball [8] Frown [:(] Shy [8)]
Shocked [:0] Angry [:(!] Dead [xx(] Sleepy [|)]
Kisses [:X] Approve [^] Disapprove [V] Question [?]

 
   

T O P I C    R E V I E W
ShelGame Posted - 10/21/2017 : 11:15:17
I originally bought an old ActionBent High Racer frame from Warren for my sons to ride. But, it's too tall and too long for my younger son. I planned to put shorter wheels on it (451 or 520) so he could reach the ground, but I couldn't find anyone to modify the aluminum frame the way I wanted it done.

The 2nd ABHR I bought from Jerry will fit my older son now just fine.

So, instead of modifying the 2nd AB frame, I'll just build my younger son a proper fitting high racer.

Here's the plan:


It's drawn to fit both 520's and 559's (as he grows). Hopefully, he'll be able to ride this for a few years before he outgrows it.

Cut tubes last night, going to start fitting pieces up today and hopefully get the main boom brazed up this weekend.
25   L A T E S T    R E P L I E S    (Newest First)
Jerry Posted - 05/15/2018 : 17:20:57
Kids can adapt very fast. Look at Tiger Woods. I saw him on TV when he was 2, he had a golf club in his hands. If your son stays interested, he could be a world champion one day. That would be way cool!
ShelGame Posted - 05/15/2018 : 07:15:57
It is. He really loves the bike, too. He rode it another ~4miles last night around the neighborhood. He just hops on and rides off like it was any other bike. Kids can just adapt to anything.

Next step will be getting him on Thom's program and making him fast!
Jerry Posted - 05/14/2018 : 06:43:44
That has to be a great feeling. Congratulations Rob. Maybe you have a future Charlie Ollinger or Florian Kowalik in the making! Good luck at Waterford.
ShelGame Posted - 05/13/2018 : 19:13:20
Got the modified Rans all finished this afternoon. Pretty cool to watch my son push off and ride away. He will be riding it at Waterford next weekend...
SpiderMonkey Posted - 04/16/2018 : 17:34:44
Nice. I was going to try something similar with a used Giro 26 I picked up. (I was thinking of cutting it then using CF to bond it back together.)

Looked like it wouldn't work out even if I did cut it, and it was in almost perfect condition, so I cleaned it up and sold it to a colleague, had AD Carson make kid 'bent #1, while I ponder if I'm clever enough to make the next.


--SpiderMonkey
Garrie L Hill Posted - 04/15/2018 : 19:13:20
Huzzah! Another Junior Class racer!

Garrie "carbon based lifeform" Hill
HPRA Co-Dictator of the East
for pics of some of my time and money sucking projects
http://s58.photobucket.com/albums/g277/cfbb/
and videos
http://vimeo.com/5513519


ShelGame Posted - 04/15/2018 : 15:54:27
And, here is my middle son training for Waterford on mom's bike...

ShelGame Posted - 04/15/2018 : 15:53:01
Frame is now painted. Assembly has started.

Waiting for some new spokes, the ones I had were ~4mm too long especially on the short side of the wheels. And, some other odds and ends.

I think this will come out nicely. Had the boy sit on it to check foot reach, and he can touch when sitting up; and he can sit up inside the tweener bars.

ShelGame Posted - 04/05/2018 : 13:13:40
Good idea. Wish I had thought of it before I brazed it back up.

What I did to re-align the boom to the rest of the frame; I found a broom handle that was a tight fit into the head tube, and I clamped a board to it and to the front derailleur post. Measuring now, I get 0.0-0.1 degree between them (my digital level only goes to 1 dec place and it toggles between 0 and .1). I'll call it good.

With a straight edge, there's no noticeable bend in the boom side to side. But, there is a very slight upward bend in the boom now. I brazed the top of the tube first, and it pulled up. I pulled it back down when I tacked the bottom, but there's still a small pull.

Your jig idea would have certainly helped...
Jerry Posted - 04/05/2018 : 10:04:10
/img]
/img]
/img]

All I had was some wood and PVC conduit. But it shows what the jig will look like and how it holds the pieces perfect. The longer you can make each leg of the jig, the better. I hope this will help.

Make sure to tack to the longer piece of tubing/pipe.
Jerry Posted - 04/05/2018 : 09:59:02
I will give you a tip we used for over 50 years fabricating and re-working pipe and square pipe and tubing. Always take a center punch and put match marks top and bottom on both pieces to be welded/brazed back together. Then take either angle iron or flat steel and braze/tack weld to at least 3 points on round and all 4 on square or rectangle pipe/tubing. Only braze/tack weld the angle/flat iron to one piece to be brazed/welded. The angle or flat steel should be a minimum 3" long, half on each side of the pieces to be joined. Longer is better! If there is enough room, I like to use at least 6" pieces. Tack weld/braze about 1/4"-1/2" in between the angle iron or flat steel. Let cool down. Braze/weld up to the angle/flat steel. Let cool down and break or grind off the angle/flat iron and finish brazing/welding. Guarantee you it will be straight. plumb, and square. Pictures of said jig coming soon!
ShelGame Posted - 04/04/2018 : 13:49:43
Brand new frame cut and welded...

ShelGame Posted - 03/30/2018 : 19:53:07
I must’ve gotten lucky with my LWB bike. It’s really close to square front to rear.

Planning an 8020 jig before I build another.
warren Posted - 03/30/2018 : 12:44:17
Yeah, I have had many issues with alignment, even with the jig I made. The latest issue was with the trike I am working on. One of the front wheel headlines was off a bit. Yesterday I fixed it, but it was a PITA! Hang in there, anything worth doing is worth re-doing a few times. Good luck with the f5 frame!
ShelGame Posted - 03/25/2018 : 20:11:35
Jr. High Racer Take 2.

Since I clearly need a decent jig before I try to build another HR, maybe I can modify one.



What have we here? A Rans Enduro 26. I measured up the frame, and with the same fork, I get just about the same geometry. Wheelbase is a hair shorter, trail too. But, workable. The real problem is, the boom is wayyy to long for a short rider. To fit the pedals, we’d have to move the seat so far forward, the the seat bottom would be almost 26” off the ground. The wrong direction for a short rider.

To get the seat back down, the boom needs to be shorter. About 3” shorter.




All it needs is a little heat, and some liberally applied brass and it should be good to go.

Someone may ask why not make it an adjustable boom, but I don’t think he needs both the seat and boom adjustable. Plus, making this boom adjustable would be more complicated.
ShelGame Posted - 03/06/2018 : 07:12:08
Well, this was a waste of time. My jig was not good enough, it seems. The rear triangle is all out of whack. It leans way too far to the left, and ,the rear wheel is angled in the opposite direction. So, if I straighten the wheel, it move MORE to the left.

Throwing the towel in on this jumble of tubing until I can build a proper bike jig (like 8020 stuff).

Instead, I'm buying my son another F5 frame and see if we can make it work...
ShelGame Posted - 02/10/2018 : 19:11:35
Brass? Or maybe flux over the brass? I haven’t cleaned it up yet...
Speedbiker Posted - 02/10/2018 : 18:10:31
Looking good! What's that yellowish goop?
ShelGame Posted - 02/10/2018 : 11:51:32
Threw some wheels on just to get a look at it on the ground. Seat height looks like it will be between 22 and 23in.

ShelGame Posted - 02/08/2018 : 09:25:04
Got a lot of brazing done last night. Then ran out of gas. Need to finish up brazing the inner portion of the rear drops, then add cable stops and a boom clamp.







ShelGame Posted - 02/04/2018 : 16:07:05
Got all the tubes fitted. And, got the drops slotted and fitted the derailleur hanger. Was all ready to braze it up, but my daughter called me in to watch the Puppy Bowl. Maybe later...




ShelGame Posted - 02/04/2018 : 09:05:50
quote:
Originally posted by Speedbiker

I can't wait to see your lowracer build!



I have a sketch. I need to think about it some more before posting it. The design is not as clean as I want yet.
ShelGame Posted - 02/04/2018 : 09:00:31
Fitted up one of the ‘seat stays’ last night to see how that miter could work out. I think it will work well. Just need to do the other one to match, and then slot the drops before brazing. I hope to get it all tacked up before the ‘Big Game’ tonight...



Speedbiker Posted - 02/03/2018 : 19:02:23
I can't wait to see your lowracer build!
PUGZCAT Posted - 02/02/2018 : 17:44:38
Another ultra sano project!

www.recumbents.com © 2017 www.recumbents.com Go To Top Of Page
Snitz Forums 2000