Custom Fighters - Custom Streetfighter Motorcycle Forum banner
221 - 240 of 244 Posts

·
Registered
Joined
·
366 Posts
Discussion Starter · #221 ·
Thanks Yan...will put some pics up when tube gets here...sent guy a crap drawing to know where to stick the bends...if all goes fuckery i shall be in touch with you to rescue me!
Tell me more about the threaded bungs idea please amd the rose joints...remember my brain doesn't speak engineer...visuals better. I did originally want a detachable subframe but didnt think i could pull it off. I do have a professional welder on my team should i need one.

Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #223 ·
Oh i see. Some round bar, tapped and maybe even weld a captive nut at the back and then weld to the frame. Hmmm...this may be a good back up plan...thanks Yan.

Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #224 ·
My Renthals turned up so just clamped them on the top yoke to see what height risers i will need...looking likely eother 30mm or 40mm. I am gping to try and perch myself over the bike in some kind of seating position, get my motorcycle hating wife to take some photos so i can get an idea visually and by feel whether the peg mounts i made are too far back...if they are i have some wiggle room to adjust.
Whilst i wait for tube to turn up i have been given a propane garage heater i am going to give some love to.


Sent from my SM-G780F using Tapatalk
 

·
Member
Joined
·
10,893 Posts
Oh i see. Some round bar, tapped and maybe even weld a captive nut at the back and then weld to the frame. Hmmm...this may be a good back up plan...thanks Yan.

Sent from my SM-G780F using Tapatalk
doing it that way, weld the nut to the round bar, drill through the nut, then tap through the nut, to give one thread. Or drill the round bar, use the tapping drill to align the nut while welding and then tap through the nut.

either way, tap through the nut after welding
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #226 ·
So some of the tubes arrived today and although i havent done a proper stick them on the frame observation...but...is there an issue from a welding perspective if I decided to switch around the subframe tubes that were initially destined for the top rail and have them welded to the lower rail whose diameter is slighly less and vice versa? Does that make any sense? Thanks.


Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
104 Posts
I take it, you're going to be putting sleeves in the tubes to mate the tube and frame?
If so, not a problem, as you just make the sleeves to suit the tube/frame where you're puu them.
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #228 ·
Thats correct...the shorter unbent tubes in the photo are the sleeves/slugs that will go into the frame that the bent tubes will slip over.
The subframe tubes are quite close in diameter so they touch the frame. I will bugger about with them and put some close up photos.

Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #229 ·
I put a temp slug in the frame, wedged in with carboard to try and hold the subframe tube at an approximate angle. This is the 25° bend and was originally for the lower subframe rails so is slightly smaller in diameter than the top rail where I have positioned in these photos. Anything obviously not going to work from a welding point of view?
Also, how tight does a frame slug need to be as the top rail of the main tube has a flat on the inside which gives it a D shaped profile when looking directly into it?


Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #230 ·
Okay so that was my 25° bent top tube, now for the 10° bend.
Same considerations...anything likely to cause a problem from a welding perspective? Might need to ever so slightly take a slither out of the subframe tube to get a slightly better angle as i am not sure whether 10° is too shallow. I think i am leaning toward the 25° bend for the top rail however the 10° one on the bottom coupd end up too long where both top and bottom subframe tubes meet. I guess i can change the angle as mentioned above to alter its angle.
I dont really want the seat to end too far beyond the rear wheel axle and certainly not looking for the stereotypical German fighter look.


Sent from my SM-G780F using Tapatalk
 

·
Member
Joined
·
10,893 Posts
run some weld around the slug and fit it to the inside of the frame with an angle grinder, perhaps two runs. drill hole through the frame and pocket weld into it, then weld the slug in place around the cut and then slide the subframe rails on and weld them on .

that's my initial thoughts
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #232 ·
Thanks Yan, your input invaluable as always.

What do we think to the angle the seat is at? 10 or 25 degrees? There's no real way to test it out with a mock up that will be strong enough for me to sit on.

Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #234 ·
That's the way i am leaning...hmmm...gonna try and do a better mock up by breaking out the duct tape

Sent from my SM-G780F using Tapatalk
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #235 ·
String and tape cane to my rescue. Sure that this is the right angle...the 20° one. Think it will work.
And i also think that the subframe line works with the seat although there might be a bit of a gap where seat and frame meet.


Sent from my SM-G780F using Tapatalk
 

·
Member
Joined
·
10,893 Posts
i'd have been inclined to weld lugs where you've cut the top tubes and made removable subframe, then you could angle the rail to properly follow the bottom of the seat at the angle you choose. Get the top rails tacked up first, set the angle and then measure up and fit the lower rails. Weld on lugs to use the holes in the seat to attach it
 

·
Registered
Joined
·
366 Posts
Discussion Starter · #237 · (Edited)
There are so many ways to skin this cat i am learning. i did try to draw what i think you mean but failed miserably...i am an absolute novice fabricator...and illustrator...and also Autistic so find conceptualising things like this really difficult.

so are my tubes redundant doing what i think you mean? are you suggesting blanking the top frame rails and weld some kind of tab in its place with a bolt hole? and then weld something similar to the end of the subframe tube and bolt together? like these photos?
Automotive tire Bicycle accessory Bicycle part Bicycle tire Rim


Tire Wheel Crankset Bicycle frame Bicycle tire


if i could have a removable subframe that would be preferred.

i came across an ebay auction listing various frame tabs...not sure what these are like as it seems a little cheap...tabs

i do really appreciate your help guys...when this is eventually built it will have been a joint effort.
 
221 - 240 of 244 Posts
Top