ADVrider

Go Back   ADVrider > Bikes > Some Assembly Required
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-13-2013, 08:26 AM   #1
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
CB900 Scrambler w/ Vids

So... I'm building a vintage scrambler/adventure/back roads/race bike. The starting point is a 1979 CB750K with a 1981 CB900F motor. I picked it up 4/12/2013 on the local CL for a few hundred bucks because it wasn't running. It has been sitting for the past 10 yrs.


Here's the back story.

I'm a bit of a moto blog junky and check up on bikeexif, pipeburn, thekneeslider ... a few times a week at least. This has led to a burning itch to do a vintage build of my own so it was only a matter of time. I'm a huge fan of the scrambler and brat bikes by the likes of CRD, LHS, Wrench Monkeies etc. so that's my inspiration.



I have the urge to hoon a bike of this design like this:





(yeah, I know they aren't Hondas. I'll make some Honda videos when it's done )


Here's more why:
I got back into riding in 2011 after a 4-5 year break by getting a street legal DRZ400E. It definitely felt like I was getting back to my roots of riding dirtbikes all the time as a kid. Since then I have ridden all sorts of dual sport oriented rides, lots of technical trail riding and some longer multiday adventure rides in CO and WY.

In 2012 I decided to give racing a try and chose RallyMoto as the way to do it. It's stage rally format like you may have seen with Rally cars. Full speed on closed back country roads! Stages are between 3 and 20 miles long It's a total hoot. http://rallymoto.com/ http://nasarallysport.com

Here's what it usually looks like from the riders seat.


My first race was on sand in at SandBlast Rally in SC.


The next one was Rally WV at Snowshoe, WV. I upgraded to a KTm 450XC-W mid season in 12.


I'm not one of the fast guys but I have tons of fun doing it. One of the neat things about this type of racing is that there are classes for all sizes of bikes so you have everything from 250 four stroke trail bikes to BMW boxers racing for overall points and against similar sized bikes for weight class points.

For RallyWV 2013 I decided to enter the heavy class (750.1cc+) so I'll be putting some knobby rubber on the CB and hitting the gravel to go at it with my buddies on big bikes.



More to come...

Entrepre-neer screwed with this post 07-02-2013 at 06:18 AM
Entrepre-neer is offline   Reply With Quote
Old 05-13-2013, 08:33 AM   #2
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
CB900 Scrambler / Racer - Now with 150% more video

I started this build log over on DTT and I'm going to start posting it in parallel over here. I'll get it all copied over in the next few days so all my ADV buddies can get the action while they are here.

The plan is to break this build up into two stages. The first sage is just getting the bike on the road for as little money as possible. The second stage throughout the summer will be performance upgrades like suspension, brakes and maybe a set of flat slide carbs.

The bike sat for 9 years so a carb rebuild is in order as well as knocking the dust and rust off all sorts of bits. I'm painting the wheels and frame satin black. Some bits will be left silver as accents. the tank will be red on top with black on the lower area below the body line.

Week 1
I started with easy stuff and disassembled from front to back while waiting for the carb kit and new carb boots to arrive.


Needed new fork seals but the wheel bearings and brakes were good.


The caliper was pretty crusty. This is after some work with a wire brush. That pile of debris at the bottom is what came off these things.


I took everything to work and hit it with the bead blaster. Love that thing!
You can tell by the caliper half and lower tree I hadn't done yet just how pristine it makes gritty parts. I spent lots of time taping off areas that I didn't want covered in beads. Also, I ran bolts into any threaded areas to keep the grit out as well.


The tires where hard as a rock so rather than wrestle them off the rim I cut a chunk out wit a band saw then cut the steel belt in the bead with a cutoff wheel.




While waiting for the carb kit to arrive I pulled them off and dropped the bowls to see what I was up against.

Not great but I've seen worse.


Entrepre-neer screwed with this post 06-28-2013 at 07:45 PM
Entrepre-neer is offline   Reply With Quote
Old 05-13-2013, 10:21 AM   #3
Highside>Lowside
Hairier Than Thou
 
Highside>Lowside's Avatar
 
Joined: Mar 2010
Location: ChiTown
Oddometer: 1,053
Quote:
Originally Posted by Entrepre-neer View Post


I live how your bike has turned out!


Signed-

The Future.
__________________
00 M944,95 620RXC,82 FT500,85 V65 Sabre,01 1150GS,82 XJ650r,91 XV920r,82 V50 Monza,77 TT500, R75/6, etc...
Highside>Lowside is online now   Reply With Quote
Old 05-13-2013, 12:42 PM   #4
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Quote:
Originally Posted by Highside>Lowside View Post
I live how your bike has turned out!


Signed-

The Future.


Longest build thread e-v-e-r.

(Note the messed up date imprint on the first image...10/01/2025)

Nothing gets by the discerning ADV crowd! Nothing!

The funny thing is that's actually the Craigslist photo from the PO. I didn't bother taking pics before tearing into it.
Entrepre-neer is offline   Reply With Quote
Old 05-13-2013, 12:49 PM   #5
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Coffee break

Week 2
The carb kit arrived so I set up my work station on a card table in the living room. The carbs on the 900 are Keihin VM43B.



I managed to delete the pics I had of the all those tiny parts everywere but I can say that next time I have a set that needs a full tear down I'll probably send them off. ;) It is good to know how these carbs work in and out though and it should make future tuning an easier process.
Here's what was left behind after the fact.



I ordered the wrong kit from e-bay so I had to wait for a new accelerator pump diaphram and fuel rail o-rings befor final assembly.

In the mean time I got the wheels painted and the new tires mounted.


The color is satin black.

I got brave and started detabbing and did some chopping too. I love running an angle grinder.

As you can see a little here I cut down the countershaft cover a bit too so I can inspect the CS sprocket without removing the cover.



Swingarm and other misc parts went to the bead blast cabinet.

Here's a quick video of blasting the swingarm.
http://www.flickr.com/photos/27840566@N05/8710938197/
Entrepre-neer is offline   Reply With Quote
Old 05-13-2013, 03:04 PM   #6
dakman74
moto-butcher expert
 
Joined: Apr 2013
Location: Los Alamos, NM
Oddometer: 46
That Left Hand Cycles CB750 you posted at the top (the OD green one) is sort of inspiration for my XV920. Right now it's even sitting in OD green (rattle-can paintjob, but oh well it'll get dropped and scratched so I don't care). My build thread is in this same section.

Some of the "for show" stuff on the LHC CB750 are kind of goofy (lack of back brake for one) but I'm digging the minimalist nature of it.

Enjoy the project!
__________________
F-it...let's ride!
dakman74 is offline   Reply With Quote
Old 05-14-2013, 08:33 AM   #7
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Quote:
Originally Posted by dakman74 View Post
That Left Hand Cycles CB750 you posted at the top (the OD green one) is sort of inspiration for my XV920. Right now it's even sitting in OD green (rattle-can paintjob, but oh well it'll get dropped and scratched so I don't care). My build thread is in this same section.

Some of the "for show" stuff on the LHC CB750 are kind of goofy (lack of back brake for one) but I'm digging the minimalist nature of it.

Enjoy the project!
I did the frame and wheels on mine in rattle can. I know I'm going to take it places it doesn't belong and any coating will get damaged. Rattle can is easy to touch up.

Can't imagine no rear brake. The LHS shock mounts are probably ok for pub hopping but mine will be made right for taking this thing off some sweet jumps.
Entrepre-neer is offline   Reply With Quote
Old 05-20-2013, 07:28 AM   #8
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Back to work...

Went out for a couple days of trail riding this weekend (Hanging Rock 200) but I'll be back to building tonight.

Entrepre-neer is offline   Reply With Quote
Old 05-20-2013, 07:33 AM   #9
yokesman
Gnarly Adventurer
 
Joined: Sep 2008
Oddometer: 459
to do the lettering,use a hard roller to apply the paint.
yokesman is online now   Reply With Quote
Old 05-20-2013, 10:20 AM   #10
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Quote:
Originally Posted by yokesman View Post
to do the lettering,use a hard roller to apply the paint.
That's a great idea. I'll have to raid my wifes craft room to see if she has any small rollers or some stamp rubber.
Entrepre-neer is offline   Reply With Quote
Old 05-21-2013, 11:23 AM   #11
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
Monday evening build progess...

It was hot and dry out when I got home so I decide to work on the tank.

I layed down some red Duplicolor Metal Specks over light grey primer. Putting it over a light color made it a little too magenta. I'm going to sand it then put some red Duplicolor Metalcast on it to get more of a candy red tone. If I still don't like it I'm going to cover it in a layer of silver and then do the Metalcast.
The lower area below the body line will still be satin black either way.

The inner fender is trimmed to its final dimensions. Pretty inconspicuous so I'll keep it.



I put a spare seat cover from a dirtbike seat on while the leather seat is being made. Fits pretty well actually and nice and grippy



I thougth I had a solution I liked for tail light/license plate bracket but it sat too high. I'm going to patch those holes and weld a plate that puts it all a little lower

I tried a few mock-ups of an oil cooler mount. I decided to try them in some scrap HDPE because I can cut and shape it more quickly. I'm going to drill and tap the frame to mount the final product which will be aluminum. I'm going to shape it to match the ears on the oil cooler.
Entrepre-neer is offline   Reply With Quote
Old 05-21-2013, 01:13 PM   #12
dakman74
moto-butcher expert
 
Joined: Apr 2013
Location: Los Alamos, NM
Oddometer: 46
Quote:
Originally Posted by Entrepre-neer View Post
Monday evening build progess...



I thougth I had a solution I liked for tail light/license plate bracket but it sat too high. I'm going to patch those holes and weld a plate that puts it all a little lower
I like the dual cat-eye taillight and license plate bracket that i got off ebay. I even got it wired for turn signals. :-D

I followed a guy into town the other day on a KTM "enduro"...almost more of a supermoto, but it wasn't the supermoto model...that had this like 6 or 7 LED taillight with a plate bracket below it, and if you looked REALLY hard you could see that the outermost LED was blinking to orange when he had the turn signals on. I guess if that'll keep you "legal" then whatever, but I was right behind him at the stoplight on my bike and could just barely make it out. Might be more visible at night, but the only thought in my mind was...if you can't really see it, what's the point?

Looking good...can't wait to see the finished project! Definitely a lot more refined than my "rattle-can rat bike" will be. ;-) Actually debating on adding some cheap graphics to my tank...either the totally cliche shark teeth, or maybe a couple of Misfits skulls...leaning towards the skulls...in fact even leaning towards adding those to my flat black CJ5!
__________________
F-it...let's ride!
dakman74 is offline   Reply With Quote
Old 07-09-2013, 03:12 PM   #13
slowpoke69
Gnarly Adventurer
 
slowpoke69's Avatar
 
Joined: Feb 2010
Location: So. Jersey
Oddometer: 489
Vaseline too

Quote:
Originally Posted by yokesman View Post
to do the lettering,use a hard roller to apply the paint.
If you put Vaseline on the surface you don't want painted it cleans up easily. I'm sure you have that around...if your boss is anything like most!

This is almost exactly what I'm doing to my 82 cb750f/ss. I've been waiting for the kids to be gone, close enough, all outta school, maybe now daddy can have a toy or 3!

I'm goin' with either the xr or drz front end, whole thing if possible, I think a single shock. Hell I'll lose some lbs. just on those two mods. I'm keepin' the 4 into 2, sexy sounding beast, especially w/supertrapps!

You got me motivated now, just got my new stator the other day, check the rest of the electrical and I'll be able to light her up!

slowpoke69 screwed with this post 07-09-2013 at 08:10 PM
slowpoke69 is offline   Reply With Quote
Old 07-09-2013, 08:45 PM   #14
Wile_E
n00b
 
Wile_E's Avatar
 
Joined: Jun 2008
Location: Missouri
Oddometer: 7
You've got boxes

After much delay, XR650R front end is headed your way.



Speaking of delay, what took so long? I was using my free cycle time to prep the sub-sonic swine for hare scramblin' on the 4th of July. Now that all that is wrapped up, I got everything sorted and stuffed into cardboard. It looks like someone might have hit something really hard with the front wheel, just sayin.

__________________
-R is for awesome -
Wile_E is offline   Reply With Quote
Old 05-24-2013, 09:44 AM   #15
Entrepre-neer OP
Ultimate Tight A$$
 
Entrepre-neer's Avatar
 
Joined: Mar 2009
Location: SW Ohio
Oddometer: 423
I can taste it...the closeness.

So close I can taste it.



Wheels, fender, chain, swingarm, shocks, handlebars, grips, side cover, levers....all assembled and given proper torque.

Epoxyied the magnet for the speedo pickup to the rotor and tested it out. Bingo.

This kit came with a thermostat that goes under a spark plug. Any thougths on that? I'm not convinced I like the idea.

I finally made a battery box mount that will do for now. I pulled it out to paint it before I took pics so more on that later. I cut away all but the basics of the old stock battery cage and welded a couple of hooks that go under the rear motor mount. It all fits under the pods and keeps the rear triangle clear so that's a win. I was close to doing a swingarm mount but the look and the potential abuse of unpaved back roads convinced me otherwise. When I make an airbox I will probably have to change this setup but this will get me on the road.

Exhaust wrap installed. Just have to mount them back up. The rear exhaust brackets and the passenger pegs got paint last night so I had to wait.


Mounted the crash bars. They took some massaging with a 2lb hammer to get them to line up. I still need 2 more bolts to tie into the front motor mounts. The ones used in the motor swap were too short to make the stretch.


So what's left?

Install the pipes
Intall carbs with clamps
Install coils and plug wires
Install harness and secure
Install guage and solder dash light connections
Intall battery box and battery
Start bike and sync carbs
Install two final bolts for crash bars
Satin paint and pinstripe on tank
Install tank
Install seat
Mount license plate
Ride

Sounds like a nice Friday evening!!! Before a long weekend.
Entrepre-neer is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 08:31 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014