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Discussion Starter #1
Haven’t done the zip tie front fork sag test yet but I will do the loaded /unloaded measurements ect after it’s together , just asking if anyone has found the need too change out the spring (don’t really want too) or spun up spring spacers on a lathe (if yes length ? ) which I can do , for a 2000ish R1 front end on a Virago 920 build , I have an feeling it a little soft ,
2nd question bike looks a little low to the ground from the bottom of the engine when down on the two wheels for my liking , installed a used Triumph monoshock that was the same length as the original air shock in the same mounts (stiff as hell BTW no sag ), thinking of milling up and welding a new swing arm shock mount to add 2-3” to push the back end down to accomplish this ?? Any measurements out there on overall mount to mount on this kind of build , I do realize is a combination of aesthetics/ geometry and performance, I’m looking for all three lol
Old mechanic Dude
Don’t hold back got thick sun wrinkled skin lol
 

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2000ish R1 front end on a Virago 920 build and it feels under-sprung? That don't seem likely,
yes the Virago is carrying extra weight, but nobody is going to stuff one into a corner like you would an R1,
never heard of the R1 being under-sprung in the front, have you?

Is it a progressive or linear rate spring?
... putting spacers in there isn't going to change the spring rate, only the preload and that will become apparent if it tops out constantly.

The rear is stiff as hell no sag, makes sense if you are building a high performance bike with 100+ hp on tap.
:| Virago is a slug of a motor, you've got nothing there to make her stand up on its tail coming out of corners under hard acceleration.
Extending that setup by 2 or 3 inches sounds extreme to say the least.

Sorry but no idea what aesthetics has to do with suspension setup, for me it needs working geometry and performance, or it's not really a motorcycle it's just a rolling art project.
... would you seriously make a bike handle less effectively for the sake of appearance? :confused:
 

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Discussion Starter #3 (Edited)
Not sure about the spring rates have to look them up and compare when I do the seals, were you thinking I was stretching the swing arm 3-4 "? I'm looking to Jack up the rear end a little for ground clearance , I will read up on motorcycle geometry, rather get it right than dead.I shoot for dead solid mechanical first then lipstick .I should probably drive it first to see if it handles well before making any changes , just shooting for safe solid handling for what it is.Owned sport bikes over the yrs have an idea of how bikes handle. Just don't want to scrape a new oil drain hole.,and your right a lot of the builds on the net are for pictures art first which attracts a lot of people ,it did me but the more I get into the rabbit hole the more I learn the difference between form and function.
Just read the thread roast lol on a 920 build LMAO hmm look away nothing to see here move along .No fishing allowed with shinny lures FML
 

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You can tell the type of spring just by looking at it:


From your description I read it you are lengthening the shock and not the swing-arm.
If you were to lay the shocks down, that would effectively reduce your spring rate because the swingarm would have more leverage against the spring.
If you just make the shock body longer you are changing the range of motion on the swingarm only in one direction, the bike will sit higher and the shock will effectively bottom out earlier.
... that is rarely a good suspension concept to pursue unless your bike is crazy low in the ass end like a Harley bagger or something equally absurd to begin with.


"Just read the thread roast lol on a 920 build LMAO" <- you only found one of them? there should be several with pretty much the same results.
Virago is a popular turd to modify to the point of being two oversized wheels held together by the motor and one of the most marginal frames Yamaha ever devised.
 

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Discussion Starter #6
Looking low is just a preliminary observation on my part, I’m going to do the math when it’s done and do some comparisons with other unmolested bikes. I miss my first road bike at 16 , it was a old Kawa triple 2 stroke with terrible handling /firecracker with hockey puck rubber . It would be worth more than the 600 I payed for it back then.putting that engine in a set up that handles would be interesting.Back to polishing my twin Turd 💩 lol
Hey TrialsRider Tks for the spring rate pic and input, the fulcrum change result wasn’t on my radar .
 

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Discussion Starter #8 (Edited)
Not on the road yet , but it runs now I’ll list what I have done to this point
Removed the 920 motor and installed a1000 in the 920 mono shock frame
Cut/punched out seized rear swing arm and installed new bearings-bushing/bolt
Fixed rear cylinder grounded pick up coil wire
Cleaned up single carb set up and installed
R1 front end mounted-new spindle/break pads-seals and new fork oil
Ripped out wiring harness and reworked for Motogadget V2
Bead blasted triple tree mounts and rear swing arm and painted
Wired in GP knock off speedo/Tach,3D printed mount
New oil/spark plugs
Remounted coils
New stainless front break lines
Fitted newer updated mono shock
Fabed new small mount break fluid cup
Fit a rear rim/wheel from a 1000cc
I do all my own work , just a parts waiting game now - should be ready to go December then I’m going to cobble together another one from the left overs
 

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Discussion Starter #10
Hey just got a call from MADD exhaust in the Netherlands my pipes are airborne, wooohooo the last of the build parts . Looks like my first time estimate was wayyyy off lol about 100 or so hrs short I recon . There should be a banner post on the forum ,”warning this is an addiction , vast amounts of time and considerable skills required “
I will post you a few pictures of the completed build .
Stu
 

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I think there are several posts about motorcycle addiction, probably real old now though so would take some searching :LOL:
 

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Discussion Starter #12
Not on the road yet , but it runs now I’ll list what I have done to this point
Removed the 920 motor and installed a1000 in the 920 mono shock frame
Cut/punched out seized rear swing arm and installed new bearings-bushing/bolt
Fixed rear cylinder grounded pick up coil wire
Cleaned up single carb set up and installed
R1 front end mounted-new spindle/break pads-seals and new fork oil
Ripped out wiring harness and reworked for Motogadget V2
Bead blasted triple tree mounts and rear swing arm and painted
Wired in GP knock off speedo/Tach,3D printed mount
New oil/spark plugs
Remounted coils
New stainless front break lines
Fitted newer updated mono shock
Fabed new small mount break fluid cup
Fit a rear rim/wheel from a 1000cc
I do all my own work , just a parts waiting game now - should be ready to go December then I’m going to cobble together another one from the left overs
View attachment 102846 View attachment 102847 View attachment 102846
 
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