Lurker's V-twin build

looks to me that the bike will go very fast [75-90 mph?]and little rake & trail might be ok on the dirt. 1920's bikes and cars were on dirt roads. they didn't know alot about r&t. but high speed with that r&t no dampner short bar's is asking for trouble. be carefull it could bite you pretty good. and you wont be the first. sorry to be the sky is falling guy but everything seems good then you hit the rite bump and oop's what happened? sorry had to say it dennis i didn't see MHF X-2
 
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motorhedfred said:
I kinda feel like a jerk for getting all this started, but if it prevents you from getting hurt or worse it's worth it.

MHF
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I am glad this topic was readdressed. I had no idea how serious having proper rake and trail was. I just assumed that is a use a standard bicycle head tube angle I would be in the clear. I am in the process of trying to figure this mess out, I know how I will go about fixing the frame but the math killin' me.

Here a drawing of my new geometry over a photo of the bike.
the previous head tube angle was 72 degrees and the new head tube angle is 66 that is a 7 degree change. This should give me at least 2 inches of trail.

Take a look and let me know what you think. I really appreciate everyones help and concern with this issue.
 

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Much better looking!!, even makes the frame look better between the head tube and tank, not so much dead space, don't get me wrong you do fine work! but the alteration would better suite the astetics (look) and function.
 
See Lurker, this is what happens when you put the most powerful bad A$$ engine you can find in a motorbike, Lol. Nobody want to see you die so you can build again. :)
 
Bigboy said:
You always use the pivot point - HEAD TUBE - !
Always measure on the bike directly! Doing math on paper
can hide flaws in the end result! (two strings, tape and a ruler!)
The range which will work is between 2.5 and 4 inches trail.
Back in the "good old days" they may had less.....but people
got hurt.......!

Roland
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I would go for 3 inches!

Roland
 
Here is a handy tool I found. Rake and Trail Calculator
RB Racing Rake and Trail Calculator

Just punch in your numbers and it will tell it like it is. You can change your input numbers to see what it will take for you to get to your zone.

I just did my bike with it and came to 2.28 (I said to Roland earlier that I thought it was 1.48 but I did my math wrong) It's very close to 2.5" . I'm not going to sweat 1/4". I'm happy with the handling right now.
 
Ill say it again..... we need a seperate thread with all this information in one place................ just sayin
 
cobrafreak said:
Here is a handy tool I found. Rake and Trail Calculator
RB Racing Rake and Trail Calculator

Just punch in your numbers and it will tell it like it is. You can change your input numbers to see what it will take for you to get to your zone.

I just did my bike with it and came to 2.28 (I said to Roland earlier that I thought it was 1.48 but I did my math wrong) It's very close to 2.5" . I'm not going to sweat 1/4". I'm happy with the handling right now.
Click to expand...

Nice link...but it does NOT work with springer or any leading or trailing link
front fork!!!!!!

Roland
 
I have been very, very busy working on this front end, and I finally have it "done". I still need to do some more grinding and welding but the hard stuff is over.

Here are the final measurements.
head tube angle: 63 degrees
trail: 3.5 inches

I want to thank everyone who notice my mistakes and convinced me to change them, even through all my stubbornness.
 

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Just my 2 cents, Dammnn!! that looks alot better and I like the fact that the springer doesn't follow the same angle as the forks, are you going to change that? and will its function be the same as before alterations
 
Thanks trucked, but the fork was just mocked up not actually installed. I will have to make a new linkage but the fork it self will remain the same.
 
I just had Dan at Taylar bikes re work the head tube on my merkel and as you can see from the pic's at the thread "flying merkel anyone" I had the same delima to deal with, it isn't my thread but a pic of the bike is in there, I just had to share my Merkel fetish, will post some pic's when I resize them to fit the format
Still ...Good job!
 
Lurker said:
I have been very, very busy working on this front end, and I finally have it "done". I still need to do some more grinding and welding but the hard stuff is over.

Here are the final measurements.
head tube angle: 63 degrees
trail: 3.5 inches

I want to thank everyone who notice my mistakes and convinced me to change them, even through all my stubbornness.
Click to expand...

63 Degrees? I think your tool is in the wrong direction. Most forks are between 17 Degrees and 25 Degrees. Not being SmartA$$ here, I really want to know what it is for comparison. Mine is 18 Degrees BTW.
 
I'm glad you decided to make the change. Now you'll be around to return the favor when we all make our own mistakes. I kinda like the different angle on the springer fork ! Gives it a 60s "Krazy Kustom" look.

Add some Krome and Ed Roth lettering to the tank and you're there !

Of course, then you'd have to wear a chromed Kaiser helmet with a spike on the top.......

Chrome-3-In-Spike-German-Kaiser-novlety-helmet-Motorcycle-Biker-2031400-1784733


MHF
 

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Sorry I couldn't get back to ya sooner but the pitch degree went from 18 to 24 on the Merkel head tube re-set, that should give you a good reference point
 
truckd, do you have a link to this Merkel you speak of? I am afraid I don't think I have ever seen it before.
 
Lurker, there are some pic's of it on someone eles's thread title'd
" Flying Merkel anyone " but those pic's are before the head re-fit still good pic's though shows right & Left sides,
Caught a virus that wiped out my computer when I went to visit bikeberrymotors and had to buy a new computer,soft wear & other stuff so when I get it all up then I can start a new thread, I do have some that Dan the Man sent to me via e-mail I'll try to PM them
 
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