Custom Frame For Thumper Motor

GoldenMotor.com

sparrow69

New Member
May 12, 2010
74
0
0
Detroit
The motor turned vertical should not be a problem; I plan to add a little extra oil. In principle we are just trying to keep the bearings and rod lubed. This motor has no oil pump to starve.

It’s the cooling is what concerns me since I have removed the entire sheet metal shroud.
cooling shouldn't be an issue either considering its in a moving bike. the shroud only plays a part if its stationary, but moving along at 30+mph you'll have more then enough ambient air blowing over the fins. Looks good.
 

dmb

Active Member
Dec 4, 2010
1,354
3
36
lakewood ca
if it did run too hot [it wont] you could use E85, it's got 15% gas in it. why? so people wont drink it! yep it's moonshine! ran meth. at 14-1 compression in a sprint buggy [VW] at ascott in the 70's no fan and the motor was cold to the touch, ya gotta jet up a bunch thou. no carbon at all, motors look brand new when you blow them up!
 

flex man

New Member
Feb 24, 2011
253
1
0
Woodland Hills Ca.
Have you ever seen a methenal fire .No because you cant see it burn .all of a sudden your on fire and cant see it..Cant imagine that scares me as I run pure methenal in the vette suppercharged with meth injector.....
 

culvercityclassic

Well-Known Member
Sep 27, 2009
3,115
177
63
Culver City, Ca
I worked on the frame a little today and really like the way it is going. I am using 1 ½ tubing for the main frame and ¾ for the rear section. The jig I made is awesome and works so well for alignment. I need to order some parts for fitment to proceed. I am hoping to have this bike complete with a built motor and one more surprise for willow springs that should work good if I can hold on…
 

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Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
Man I just love watching builds like this come together!! These are my favorite threads. Its gonna be sweeet (^):D
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
It's coming along nicely Jeff, I'm really liking the beefed up chain-stay junction down there! Keep it coming, it's an exciting build for sure.

dnut

I worked on the frame a little today and really like the way it is going. I am using 1 ½ tubing for the main frame and ¾ for the rear section. The jig I made is awesome and works so well for alignment. I need to order some parts for fitment to proceed. I am hoping to have this bike complete with a built motor and one more surprise for willow springs that should work good if I can hold on…
 

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
5,844
109
63
SoCal Baby!!!
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. I am hoping to have this bike complete with a built motor and one more surprise for willow springs that should work good if I can hold on
Looking good Jeff. You have some fabricating skills.

With that HF 6.5 Hp four stroke I will be rooting for you in the Willow Springs unlimited class race against the Morinis and the eBikes.

Are you running gears?

I am a thumper kinda guy lol
 
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culvercityclassic

Well-Known Member
Sep 27, 2009
3,115
177
63
Culver City, Ca
I worked on the frame today and now have the main tube for the motor mount installed. This motor will require additional motor mounts and an added torque arm to handle the power. This is a fun build but takes time and thought as to what needs to go where and if it’s really needed.

I really need to clamp down and get this completed. Someone needs to put the torch on my ass…..
 

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scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
Looking great Jeff, you gonna mount the Suzuki forks on it? Are you gonna go with 24" or 26" wheels? Just looking at the posibilities of your new sweet frame and engine set-up. Cheers bro!

dnut
 

culvercityclassic

Well-Known Member
Sep 27, 2009
3,115
177
63
Culver City, Ca
I decide to stay away from my local bar night with friends and work on the bike…also saved some cash….
Well I got the frame together using the mig and the almost new Miller Diversion 180 Tig took a **** so it’s gone in for repair, which sucks….
I am real happy with the way the bike looks…going for the Jesse Rooke look and it is headed that way.
It’s a roller now; I have to decide on the wheels….may go wide since I have the room.

Hey Scotto...no Suzuki forks...way tooooo heavy.....and going with a disk so the forks won't work.
 

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scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
Yeah I hear ya on the Suzuki fork, it weighs more than the tandem frame I'm working on, seriously. I'm putting one on the tandem though, it will handle fine on that rig with a drum brake and going disc on the rear.

I decide to stay away from my local bar night with friends and work on the bike…also saved some cash….
Well I got the frame together using the mig and the almost new Miller Diversion 180 Tig took a **** so it’s gone in for repair, which sucks….
I am real happy with the way the bike looks…going for the Jesse Rooke look and it is headed that way.
It’s a roller now; I have to decide on the wheels….may go wide since I have the room.

Hey Scotto...no Suzuki forks...way tooooo heavy.....and going with a disk so the forks won't work.
 

The 26incher

New Member
Dec 19, 2009
394
2
0
Pepeekeo, HI
No bottom bracket for cranks and pedals Jeff? Going for the straight mini motorcycle frame? Are you going to weld foot pegs cafe or chopper style?
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
This is my attempt to build a one off custom frame for the Dyno Thumper. http://motorbicycling.com/f41/dyno-thumper-28189.htmlThe original plan

Well it is not considered a Dyno Thumper anymore now that I will be building a custom frame for this HF motor.

I have wanted to build a one-off custom frame for awhile and now is the perfect time to do so with this motor. I have gathered all the material and started with the drop outs, I made them out of 3/16 plate.

I picked up 20 feet of ½, ¾, 1, 1 ¼, and 1 ½ .065 tubing. I purchased a tube roller from HF and have another hydraulic bender to use; I also have a tubing notcher. I ordered head tube and bottom brackets that are really impressive, the quality is unreal.



I keep looking on Rat Rod Bike website for ideas and found some really cool home built frames. I will be going for old school Rat-Bobber-Drag Bike style. This is the look I really like....
Falcon Motorcycles : Hand Made Motorcycles Custom Designed Around Rare Iconic British Engines

I will keep this post going as I progress….
I'm sure there will be pedals, he just hasn't welded the BB on yet.

dnut
 

tomgndallas

New Member
Sep 19, 2010
132
0
0
Dallas, TX
just picked up a harbor freight motor myself. I have been pondering an engine for a long time now. the local shop had the 6.5 for 94, i brought in the web price of 74 and they honored it. Lightweight engine too, very cool. Now its time to choose a frame and get started on a long project. I still have a 69 CB450 project I need to finish before I get started on the MB project...

Hey Sportscar Pat, if you read this, ever think of making a drop loop or sportsman frame for this little motor? I got cash in the paypal account!