26 inch DYNO FrankenBMX. FIRST RIDE! SERIOUS FUN!

[LukeTheJoker]

Some of you may have seen the thread I started trying to decide if I wanted a big BMX and if I did, which of the ones I posted people would recommend. It ended up on that thread that I decided to build my own out of some parts I have available to me here. My goal being to make a bigger version of the early Redline and DiamondBack BMX bikes I used to ride to school back in the day, bikes I used to have fun with and was comfortable on, but were obviously too small for me now...

This is where I am headed:

Started stripping out parts from my stockpile today, not included in this photo is the 26x1.75 ARAYA wheelset I will be using:

The frame is a DYNO downhill mountain bike that I will switch out the dropouts to BMX style and remove all the other unwanted rubbish from, the other hard bit will be the forks, as I don't want to run the heavy and bouncy sprung style ones, I will build my own solid 26" BMX forks out of the threadless fork stem from the original forks and a few bits and pieces I have laying around.

Nice Sugino crankset converted to single 38 tooth sprocket and some nice Dia-Compe levers:

I plan to make up some BMX style bars from some I have here and the original Mountain-bike bars:

This is how I hope to get them to turn out:

I have tried to find a pad-set to suit the frame, while I can get pads designed for 26" cruiser BMX bikes, they are all designed for smaller diameter top tubes, so I will be making my own top-tube pad and stem pad but hoping to buy a bar pad but may end up making that too so that they all match. Guess my sewing skills will be getting tried out! :lol:

Also have to make a oversize and overlength layback post, thankfully I have found a little 12" scooter whose main tube is the right diameter and has a nice bend in it, some grinding, welding and add a little brace to the back of the tube and it should be almost perfect!

Hoping to get some grinding and welding done on the frame and forks in the next couple of days, hopefully it all works out as planned.

Luke.

 

[Gold Street Customs]

Re: Mountain bike to 26" BMX Build/Conversion.

Got my attention :wink:

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build/Conversion.

Cool GoldStreet! Should be similar to ride to your buildoff bike when it is done I imagine...
(Now if I could just find a Cadillac headbadge...) :lol:

Luke.

 

[H8PVMNT]

Re: Mountain bike to 26" BMX Build/Conversion.

This should be fun... I like your bar idea I may do something along the same lines. I am going to do a frame stretch and incorporate a few MTB bits on a 20" but I had better start my own thread. Build on!

 

[LukeTheJoker]

Re: Mountain bike to 26

@lukethejoker,why not go for a 29er BMX?

Sent From My Rotary Phone

:lol: Because it would cost me money! :lol: I have everything I need here to build this bike, and all the parts work together well and are good quality, so it seems a natural fit to build it...
I may build a 29er later if I decide this is too small, but will have to buy rims, tires etc, so I am not in any rush to do that, already have all my bike bucks for the next 6 months committed to the 2 mini build-offs... :wink:

Luke.

Sent from my mind, through my fingers, into the ethernet and on to you.

 

[mikeeebikey]

Re: Mountain bike to 26" BMX Build/Conversion.

You don't have to carve the frame up to fix the dropout problem, they sell tensioners....
Or trade me something for that Dyno...It'd go nice with the collection!

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build/Conversion.

You don't have to carve the frame up to fix the dropout problem, they sell tensioners....
Or trade me something for that Dyno...It'd go nice with the collection!

Pretty sure it is a cheap frame originally, it has a "Pacific Cycles" sticker on the seat tube, so doubt it is anything special! Looking at the components that were on it, it was at best a mid-range model. Even if it was a decent high end frame, shipping from here in Australia to you would be $$$... I am aware of the tensioners that are available, and I have everything here to build my own if I wanted, but then it is still a converted Mountain bike, not a Big BMX, which is what I want to build... Does that make sense?

Sorry about the dodgy pic, it is night-time here.

Luke.

 

[mikeeebikey]

Re: Mountain bike to 26" BMX Build/Conversion.

I forget you are down under......
Dyno also had some single and multi speed cruisers that were straight tubed only steel, tanks.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build/Conversion.

So... I am ok to modify this cheap Pacific Cycles DYNO? Or are people going to get upset with me? :lol:

Luke.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build/Conversion.

Started on the forks today, took some planning as I want to keep the front ride height fairly high like it was with the sprung front end, but did not want it to look out of place, also did a lot of planning to make sure they would be as strong as possible.

Started by cutting out the threadless headstem from the old forks:

A little welding inside to make sure the bearing surface did not move when the rest of the post was cleaned up:

20" BMX forks cleaned and marked ready for cutting, 2 inner strengthening tubes from the top tube on a kids BMX and two 3 inch long extensions from another set of forks:

Holes drilled to ensure the strengthening tubes contact all the way down and add the most strength once pad welded up:

The forks I chose for this were not great quality and the dropouts were only welded on one side, fixed that:

With the inner tubes tacked to the top of the split forks and the rest assembled in place, I bolted in a spare wheel to check for straightness and length, I finished the tacking with the wheel in place to hold everything in position:

Cut a piece from and old stem and welded that into the top of the forks, made a spacer out of some heavy wall tube I had and slid the rest of the stem piece into the old fork stem, this is the piece that will add height to the front end and also add much needed strength to the top of these forks:

A quick test for looks and straightness:

Decided it was too high and looked a bit funny so cut the spacer down an inch and retested:

Much nicer! All welded up including more strengthening pad welds in the fork stem:

It would normally be time to clean these up, but I kind of like the look with the pad welds showing, may just leave them for the moment and decide when I get the rest of the bike done, part of me just wants clear coat them as they sit, this is Rat Rod Bikes after all! :lol:

Next job after some lunch is the bars, I found another stem that takes the slightly smaller bars rather than the stem I had which takes the monster size bars, so now I can just add the expanded center section from a set of Mountain bike bars to the BMX bars and it will all work, I will also add 2 inches to each end to give me some extra width, the welds will be covered by either the grips or the stem, so the bars can remain chrome!

Luke.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Got back to work after lunch, first up, welded the spacer on the the bars:

Then welded on the two inch extensions to each end of the bars:

Cleaned up and polished with a sander disc:

Front view of the bike with the bars on:

Started work on the seatpost, cut a section from a 12" scooter frame, welded the top of the old seatpost on:

Cleaned up the weld and added a supporting rod:

Seatpost in and seat on, side view:

Better side view:

Decided from those photos that the bars sat too high, so turned the stem over:

How it looks now:

Still looks a little weird, but will look better once the stem pad/cover is on. Overall very happy with how it is coming along, seems to be a good fit for me and is looking good in my opinion. Current weight as it sits is 13.2kg (29.1lbs) hope to have it all together and done for around 15kg. (33lbs)

Luke.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Found another interesting bike frame in my stash today, a Malvern Star 24" 6061 Alloy mountain bike with near horizontal dropouts, best of all it is actually longer in the top tube than the Dyno so may actually fit me when done up, unlike most 24's. I only have standard 24" mountain bike rims, no flashy Araya 7X's for this build, but it does have a standard threaded fork so I can use my BMX stem/gyro/bars combination on it... Might be an interesting build when this current one is done?

Near horizontal dropouts, which would mean no frame modifications or the need for a adjuster pulley:

Sorry about the dark photos, just gone nighttime here...

Luke.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Forgot to post this pic of the front brakes earlier:

Also, pretty sure I am going to swap the stem out for one of these when I get some $'s:

May as well grab these while I am at it:

I was originally thinking of running some 26 x 2.5 inch tires, but looking at the bike now, and considering the way I want to ride it, as well as possibly fitting the above mentioned number plate, I might change that to some 26x 1.5-1.75's... Go with the dirt racer feel.

Luke.

 

[Gold Street Customs]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Looking real good,nice fab skills.

 

[The Renaissance Man]

Re: Mountain bike to 26" BMX Build/Conversion.

It would normally be time to clean these up, but I kind of like the look with the pad welds showing, may just leave them for the moment and decide when I get the rest of the bike done, part of me just wants clear coat them as they sit, this is Rat Rod Bikes after all! :lol:

Luke.

I'm not feeling the frankenwelds. I'd vote clean it up (unless you carry the theme through out the rest of the bike). :wink:

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Thanks Gold Street and Renaissance Man, probably will be cleaning them up, was just happy with the way they came out, so figured I would look at them for a day or two first...
A friend of mine suggested that if I was buying a new stem anyway, why not get a DYNO or GT stem and matching seat for it? Well been looking around, and not liking my chances of affording them, roughly double the price of the FMF-PowerMoto ones I was looking at... Never know, if I am enjoying riding it that much and keep my eyes open, I might find some...

Luke.

 

[Pedro]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

LTJ-

I dig it. What makes me laugh is that I haven't been so active on this forum lately, and earlier in the year we chatted about dragster styled bikes... and both got started, and now my itch is a 26" BMX bike... Good taste I guess. Your progress on this is great, and this looks awesome. Nice work, I'll be watching this thread.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Hey Pedro! Good to hear from you! Hope you will post up your build on here when you get to it! I have another Dragster style build planned for the coming "Muscle Bike Build Off #02" it will be the most dragster styled bike I have done yet, wheelie bars and all! :mrgreen:

Luke.

 

[LukeTheJoker]

Re: Mountain bike to 26" BMX Build. WORK STARTED!

Progress on the bike today:

Been looking at lots of stems on eBay and the local bike shops, found out I really like the solid block, front load style ones, unfortunately the nice ones of them are rather expensive, I can get them at a reasonable price from the US, but once I pay the freight it is no longer so cheap... :roll: Started narrowing down my choices to what I could afford to spend on this very low budget build, and did not like any of the stems I found! I started thinking that throwing money at the problem is not the way I normally do things, otherwise I would have just bought a 29er Quadrangle, so I started designing my own stem out of a mountain bike stem and an old BMX quill stem, and today I built it...

This is a pic after finishing the welding but before clean up, at this point I was figuring it as a total failure, did not like the looks of it at all:

After some grinding and sanding, things started looking much more like what I had in mind:

Pretty happy with it, so tried it on the bike:

Obviously still needs more clean up and painting, but actually pretty happy with how it turned out in the end!

Luke.

 

[bigfatcat]

Re: DYNO Mountain bike to 26" BMX Build. HOME MADE STEM?

WOW! That came out amazingly dude! Love what you've got going here.