YZ-24 MotoBike ...now SOUTHERN FLYER (6th Place) *revised*

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Thanks everyone for the input on the hub. I've searched for a photo of the factory mount with every combination of words that I can think of and still no results. I will just create my own mount like I had planned to do in the first place. :|

I picked up the fork tubes from the machine shop and mocked up the fork on the bike today! I really like the way they turned out and I'm tempted to leave them as is and not polish them as planned.

The first mock up was a guess on the hight without the actual fork in place and was off by one inch. Luckily it was on the short side so I gained an inch with the latest mock up.

I've been taking measurements and plugging them into my computer model and the geometry is looking fairly good so far. I plan to move the fork drop-outs forward and now that I'm zeroing in in the stance, I should be able to get the head tube angle and calculate the fork offset for the best trail.

Like the brake mount search, the research that I've put into finding the optimum trail has not really yielded much definitive results. Generally it seems that 60mm is a good average. I'm open to suggestions! :mrgreen:

 

[OneHorsePower]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

that's one nice long fork 8)

 

[Vintagebikelover24]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

THIS BIKE IS GOING TO BE AWESOME!!!! I really can't wait to see the finished product! looks great so far

 

[kingfish254]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Found this cool Yamaha front drum that would be cool if you could figger out how to lace it.
http://www.ebay.com/itm/1978-YAMAHA-YZ8 ... 90&vxp=mtr

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

that's one nice long fork 8)

It's 5" longer than stock, but the picture makes it look longer than it really is. The YZ bikes that I'm emulating had really long forks on them also.

THIS BIKE IS GOING TO BE AWESOME!!!! I really can't wait to see the finished product! looks great so far

Thanks for the props, I can't wait to RIDE the finished product!

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Found this cool Yamaha front drum that would be cool if you could figger out how to lace it.
http://www.ebay.com/itm/1978-YAMAHA-YZ8 ... 90&vxp=mtr

That would go nicely with the Yamaha YZ theme, but I'll have a hard enough time lacing the Worksman drum!

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Been working on a brick patio the last few days and haven't been able to do anything to the MotoBike. Today however, I needed to give my back a break and also get out of the afternoon sun for a little while, so I did get one of the fork tubes welded in. I'll probably finish the other side Monday.
As usual, I depend on my cousin to take care of the Tig welding for me. I usually get everything ready and sometimes tacked in place, then turn it over to him to weld it right! He is usually working on street rods, so it works out for us to help each other when I'm at his shop.
I forgot to take my camera, but when I go back, I'll try to take some picks of the process.

 

[LukeTheJoker]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Looking forward to seeing these bad boy forks all done!

Luke.

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

The first time that I bought tires for my motocross bike as a teenager, I was surprised to learn that the front wheel was a larger diameter than the rear. I had just rode it but never payed any attention to it. I've been thinking a lot about this while trying to work out the fork mods. Once again, it hadn't occurred to me until now that I've been focused on that part of the build.

So today I stuck a 26" junk wheel up front to see how it would look. Of course the key to it is the right tires. Now I'm on a new quest to find a 24 x 3 knobby for the rear and a similar tread 26 x 2 (or less) for the front. Without a really fat tire on the rear it's not going to get the right effect.

Any suggestions would be appreciated!!!

Here's a comparison ...
24"

26"

 

[LukeTheJoker]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Totally agree, but unless you can get at least that extra inch per side on the 24, it probably would look better with both the same size, just my opinion of course...

Luke.

 

[bfelt]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

FELT bicycles sells a 24" x 3" knobby tire they call the Berm Master. I have some mounted on 2.5" Large Marge rims and they sit 26 1/2" tall and 3 1/4" wide. Vintage Iron uses them on their FELT made bicycles that look like old dirt bikes (Bultaco Pursangs, Suzuki RMs, Husqvarna's and Yamaha YZ's). The tires look like dirt knobbies. How much tire clearance do you have??

 

[jats]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

I PM'ed you about a tire

Troy

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Totally agree, but unless you can get at least that extra inch per side on the 24, it probably would look better with both the same size, just my opinion of course...

Luke.

That's my opinion also. Thanks Luke.

FELT bicycles sells a 24" x 3" knobby tire they call the Berm Master. I have some mounted on 2.5" Large Marge rims and they sit 26 1/2" tall and 3 1/4" wide. Vintage Iron uses them on their FELT made bicycles that look like old dirt bikes (Bultaco Pursangs, Suzuki RMs, Husqvarna's and Yamaha YZ's). The tires look like dirt knobbies. How much tire clearance do you have??

bfelt, that might just work. I like the fact that the 24 and the 26 match. The clearance is 3 1/4", I might would have to spread just a little.

I PM'ed you about a tire

Troy

Thanks Troy, message sent back.

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

I measured the trail and it should work out good. The 24" wheel mounted as is measured 75mm and the 26" moved forward in front of the fork (which is what I need to do for the drum hub to work) ended up at 60mm. That is the average best trail according to what I found on the web.

 

[LukeTheJoker]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Your trail sounds pretty spot on what I have read! Nice work!

Luke.

 

[jats]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

this thing is gonna look way radical you going to try to work the old style tuning fork emblem into it?

PM'ed again

Troy

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Your trail sounds pretty spot on what I have read! Nice work!

Luke.

The results are from my best guess mock-up at this point, but I'm feeling pretty confident that I'll be real close in the end. Thanks!

this thing is gonna look way radical you going to try to work the old style tuning fork emblem into it?

Troy

Thank you Troy, and yes on the emblem but that's all I'll say! Gotta save some stuff for the end! :mrgreen:

 

[jats]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

happy dance!!!!!!!

Troy

 

[jats]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

PM'ed you! let me know

Troy

 

[The Renaissance Man]

Re: bmX-RATED for ADULTS ONLY - YZ-24 MotoBike (fork tubes!)

Got the other fork tube cut out but didn't have time for anymore than that. I did remember my camera this time to show how I did it.

First I cut the tube off above and below the brace and then drilled down the center of the tube (top and bottom) with a step drill. It only needed to go deep enough to go past the weld and then it popped right out. A little cleaning up with a rasp and a rat tail file and the new tube slides right in place ready to weld.

Here's the picture from the first side after welding the new tube in...