Lurker's V-twin build

The cvt I will be using is a Comet 44 driver to a 40 driven.

The bike is estimated to do speeds somewhere in the mid to high 90's. However I don't have my hopes up. I have talked to guys who have 18hp Briggs in Chushman scooters and they say their bikes will do 75mph+ and cruise at 60 all day long. However their bikes are geared low and have much smaller wheels and tires than my bike so I wont know exactly until I get it running and take it for some test rides.

Here is a breakdown of the components I made the exhaust from.

1. Parts from exercise equipment. Found on trash night.

2. 1 1/2" x 1 1/4" galv. bushing. Found in electrical conduit section of Home Depot.

3. Mounting flange found on a wall mount horse saddle storage unit. Found at Theisen's Farm Supply on my trip to Iowa.

4. 3/4" to 1" gas pipe reducer. Found at Home Depot.
 

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Nice. It's good to recycle parts from various sources for a one off build. It ensures that you have the only bike like it in the world. It's cool to have the only one of something. I'm a watch nut. Crazy about wrist watches. I found a custom watch site and sent them a seiko of mine and had it done special and it's the only one like it on earth.
 
Lurker said:
So I got the 420 chain in the mail last night and it is huge. I tested it on a 41 sprocket, a 40/41 drum clutch, 41 Sach moped hub, and a spare sprocket that was marked 40 and it fit all of them perfectly. I want to test the 40 sprocket again because according to the measurements I found it shouldn't fit. If any of you are planning this upgrade, keep in mind not all 420 chains have a tensile strength of 5,200lbs. EK brand was the strongest I found. In the photo below you can see the 420 chain on the left and a normal 40 chain on the right.
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#41 gear is designed for chains with a .306" roller like the #415. The #420 chain has 5/16(.3125) rollers and should be mated with a #40 gear. Don't use your chain on a #41 gear. I'm not sure why your clutch is listed as a #40/#41 clutch, they're two different sizes.
 
# 41 #420 # 41 are all 1/2" pitch. All have 5/16" rollers. # 41 & #420 have1/4" width & #40 has5/16 width. #41 has a 1/8" pin and the #420 & #40 have5/32" pins. The tensile strength #41 2,000 #420 & #40 is 3,700 lbs. I hope this helps..............Curt
 
I got my cvt today, so I installed it and then spent quite a bit of time looking at the bike trying to figure out what to do with the rear cylinder exhaust. I think I have it figured out so hopefully I will be able to fab that up tomorrow.

I wish I had a bathroom scale so I could weigh this thing I can hardly pick it up now. I think buy the time this build is over I will have given myself a hernia.
 

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Is that a flanged elbow on the rear cyl? If so, I would consider turning it foreward and use graceful curving pipes facing to the front, foreward of the cvt clutch.
 
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Lurker, what is the degree of your steering angle? I was told by Timm of Big Boy Cycles that my steering angle seems a little steep. I said yes, I can't ride with the hands off the bars. He said he imagines so. I didn't know about frame geometry at the time. Anyway, your steering angle seems like mine. Can it be ridden at 20mph or so without any hands on the bars?
 
Whew. The first thing you notice is the engine. It's an awesome bike. It looks like it has a bit of muscle too, no hidin' it.
 
cobrafreak said:
Lurker, what is the degree of your steering angle? I was told by Timm of Big Boy Cycles that my steering angle seems a little steep. I said yes, I can't ride with the hands off the bars. He said he imagines so. I didn't know about frame geometry at the time. Anyway, your steering angle seems like mine. Can it be ridden at 20mph or so without any hands on the bars?
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Looking at the pic there doesnt seem to be much trail. I learned about rake and trail building a recumbent. Its a hand full with too little.
 
Im not saying you arent right Cobrafreak, but the issue of rake and trail to do with Lurkers forks were questioned already, and Lurker seemed to think they were fine if im not mistaken.....
 
I just wondered if he knew the degrees off the top of his head, no big deal. There is a magic number out there for handling and stability. I'm going to build that into my next frame project.
 
"Next frame project"??? Are you planning a second build or just talking in the future?.... dont hold out on us Cobrafreak :-)
 
Thanks for the complements and concerns.

"Whew. The first thing you notice is the engine."- I love this. That was kind of the visual goal of the bike so this statement makes me very happy.

As for the fork/headtube issue, I already discussed this a few pages back with a diagram and every thing. The headtube is exactly 74 degrees which is very steep but still within reason. When I did my push test I was able to take my hands off the bars with no problems at all. I know that it couldn't have been more than 5mph but it still felt very good. Besides at this point there isn't much I could do about the headtube angle anyway. The only real way to know if it handles well will be to get this beast running and take it for a test drive.

I really appreciate your guys concern for my safety.
 
For sure Im no expert on frame geometry, and its more critical on a recumbent with a small front wheel with reduced gyroscopic effect. I didnt realize this had been adressed already. Kudos on a great build!
 
Hey lurker when you started your build did you buy a head tube or did you make your own? If you made your head tube can you tell us the dimensions? Thanks and great build!!
 
Red Light,
I made my own using 1 1/4 tubing that is 6 1/8 tall with a 1 1/8 reducer press fitted inside of that. It was very simple to make.

Cobra Freak,
I just noticed you said "next frame project" in your lat post. What do you have in mind? Can you share with the class, or is it top secret? What ever it is I look forward to it.
 
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