Sportsman 200

GoldenMotor.com

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Pat,
I've been following along on these clone engine builds from some distance, wondering if the 200 has passed the mark of too much engine. Let me say that what you have done is remarkable and as everyone has noted, this one is a work of rolling art. My uneasiness is over the young bucks reading your thread and Cobrafreaks', Lurkers'... and of course wanting to do the same. All of you mentioned know what you're doing and have built up the rest of the bikes to the level of the engine... excellent braking, wheels, strong frames, etc. It is the kid wanting to slap the 200 into something or other, doing it all as cheaply as they can get away with and then go as fast as they can... a recipe for disaster.

I could not do what you guys have done. I don't know enough to pull it off and stay alive. On a motored bicycle the difference between 20 mph and 30 mph is considerable. Push it up to 40 and you'd better have the best of everything. Over 40 you need to be on high alert, skilled as a experienced rider and really know your machine, akin to being a NASCAR driver.

Young bucks, make no mistake. What Pat has built is a light motorcycle. If you're going for the big time motor, be sure the rest of the build is up to snuff and that you actually know what you're doing. If you don't then admit it, take your time and learn. Stay alive. I sound like the old guy that I am who knows we don't come with spare body parts. I have a traumatic brain injury from lightning and know that the last thing I need is another one from a bike crash. You wanna go really fast make sure the thing you're riding is engineered to handle it. If you can't build one like these guys are doing, then buy a motorcycle.

Sermon is over. Pardon my sticking my nose in here. I like to go fast, too. I also like to stay in one piece.

Well done, Pat. You keep raising the bar!
SB
 

oldtimer54

Member
May 15, 2010
540
6
18
On a bike
Ive got one of those 200cc engines on a firmstrong frame but I didnt build mine for speed. I built mine for hills at better then 9000 feet. It does a good job.
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
Whitey,
It's not like I am burning the tread off the tires. My concern is the speed potential of the machine verses speed rating of cruiser bicycle tires. I saw a guy at the Delta Whizz-in ride pass me at about 30 mph and his rear tire blew, came off the rim and wound up between the spokes and frame all in a split second. It locked up his rear wheel and he came skidding across the road right in front of me. It was an eye opener! He saved it and didn't go down, but it could have easily put us both on the pavement. Simplex tires are 90 mph rated and are basically light motorcycle tires. This bike needs them.

GasX,
See above. Fat Franks are good but just a bigger version of the Felt Quick Bricks. Not up to a mid 40 mph cruiser.

Motorhedfred,
I have a few of these GX200 clone engines kicking around the shop. Two of them have the gas tank front mounts, one does not. Two have four bolt valve covers, one has a five bolt cover. Those tank mounts are just funky and were at weird angles. I finally went with the four bolt holes on the output shaft side cover to attach my front mount as it seemed the best solution.

Dagwood,
If I remember correctly I am currently at 12.44:1. Primary is 12-38 and secondary is 13-52 as I recall. I also cut a 48t rear to replace the 52t depending on riding conditions. Don't really want to make the bike faster on the top end but right now it's doing little wheelies and can chirp the rear tire. I notice little burnout marks in some of my videos! As for clutch slippage, there really is none. It is just not a slipper design to keep the rpms up till your rolling. Quite the opposite. I roll into the throttle, it grabs, and off I go under full clutch lock. More like a manual clutch in a car the way it grabs. I can't say enough about this clutch and the drive system I developed. It's the coolest part of the whole bike. I will try to get some video of the clutch working while the bike is on it's rear stand. You can clearly see the clutch actuation as it engages and disengages. When riding I am always above the 2800 rpm lock point so it stays engaged. If it drops below that I just blip the throttle.
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
Silverbear,
The wisdom you offer is appreciated. If you notice I am preaching safety in this thread. I have developed the frame as I can to withstand the torque and have also mentioned that building up these engines with cam, compression ratio increases, etc., is simply not necessary. Also notice my riding gear. It has kept up with the build. I now wear a full helmet, padded riding jacket, gloves, and boots. I give this machine the respect it deserves. I also don't ride around like an idiot. I have plenty of fast machines. Just because it can doesn't mean you have to. This is not a bike for a kid. It is a 200cc light weight motorcycle that just happens to have pedals.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
Maybe a tachometer of some sort would be smart to have considering that now you have an engine that can approach redline easily. At least for testing purposes. It would be good to know how fast the engine is actually spinning at a specific speed. I think one of the Go Kart web stores offer a small digital Tach for Karts that would be low key.
Is this low key enough?




URL=http://imageshack.us/photo/my-images/828/img0949d.jpg/]
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That is a Trail Tech tachometer/hour meter and is a vey useful instrament/tool. It works great and is a good reminder for oil changes as well. They cost $35 and are on sale frequently for $25.....cheaper than the Tiny Tach and half the size.

Nice bike Pat....we'll see you at the races?

dnut
 
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sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
Hi Scotto,
I will try to make the next races.

Darkhawk22,
I am going to give the Simplex tires another battle to install. I already paid for them.
 

culvercityclassic

Well-Known Member
Sep 27, 2009
3,115
177
63
Culver City, Ca
Pat: nice progress and R & D on the bike, it sure looks great and performs just as well. It's nice that you share all the changes you make and the reasons for them. I always take notes and keep a keen eye on them...lol

I noticed you mentioned that the clutch locks up and off you go, does it slip some-what at take-off or just lock up hard?
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
Pat: nice progress and R & D on the bike, it sure looks great and performs just as well. It's nice that you share all the changes you make and the reasons for them. I always take notes and keep a keen eye on them...lol

I noticed you mentioned that the clutch locks up and off you go, does it slip some-what at take-off or just lock up hard?
Someone once told me I over explain. It was one of my brothers so I didn't really listen. Anyway, I am told the the clutch reaches full lock at 2800 rpm. Seat of the pants tells me the first contact of the two disks to full lock is very short, maybe 400 rpm? I am sure the specs are available but don't know what they are exactly. If I nail the throttle it hooks hard. If I roll into it then it just smoothly engages and moves forward. It is fully predictable and controllable. What it does not do (like the Morini) is slip forever while the bike comes up to speed. You get what you pay for with clutches and that beautiful little piece of engineering was $300!
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
My throttle sticks on my Morini bike and I love it that way. Does two things for me ... helps with warm up when I momentary walk from the bike.. [Bike don't warm up very fast at a low idle] Last I can take my hand off the throttle set to cruise as slow as 5 miles an hour ''at times'' it seams to like about seven. Holds absolutely steady for me 10 miles an hour on up at every speed..

Its all in the carb tuning for me that made it do what I wanted it to do.. The cruise control ''sticking hand throttle'' scenario's I just described were not possible other wise. In my experience.
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
We had the 200 out today for further testing. I have had a lot of questions about the clutch and how it it works. Here is a video while the bike is sitting in the stand. You can see how the clutch engages and disengages when the engine hits 2800 rpm.
Sportsman 200 Testing Video | Flickr - Photo Sharing!
Next video shows the bike cruising at 50 -52 mph. This is not a run up to speed and then backing off. This is a comfortable 50 mph cruise on a country road. Rear sprocket is a 52t. I also have a 48t which whould bump cruise speed up to about 55 mph.
Sportsman 200 Testing Video | Flickr - Photo Sharing!
One more video at speed. This bike is a lot of fun!
Sportsman 200 Testing Video | Flickr - Photo Sharing!
 

harry76

Well-Known Member
Apr 16, 2011
2,557
47
48
Brisbane, Australia
That is just way too cool. I cant believe you guys get away with riding them over there...... im soooooo jealous................ Once again this has been an unbelievable build and your bikie has set the bar a lot higher. Great work
 

cory151

Member
Oct 19, 2010
466
0
16
SoCal
We had the 200 out today for further testing. I have had a lot of questions about the clutch and how it it works. Here is a video while the bike is sitting in the stand. You can see how the clutch engages and disengages when the engine hits 2800 rpm.
Sportsman 200 Testing Video | Flickr - Photo Sharing!
Next video shows the bike cruising at 50 -52 mph. This is not a run up to speed and then backing off. This is a comfortable 50 mph cruise on a country road. Rear sprocket is a 52t. I also have a 48t which whould bump cruise speed up to about 55 mph.
Sportsman 200 Testing Video | Flickr - Photo Sharing!
One more video at speed. This bike is a lot of fun!
Sportsman 200 Testing Video | Flickr - Photo Sharing!


As others have stated nice build yada yada, etc. As far as the motor goes I would hope it is faster than a Morini at 4x the displacement. Yet I know of no motor options that come close to the reliability of the S6s (including my GX35 bike). I was thinking of one upping everybody and doing a GX 340 build but then I decided Im not starting my bike with a shoestring. Keep up the good work.
 

harry76

Well-Known Member
Apr 16, 2011
2,557
47
48
Brisbane, Australia
As others have stated nice build yada yada, etc. As far as the motor goes I would hope it is faster than a Morini at 4x the displacement. Yet I know of no motor options that come close to the reliability of the S6s (including my GX35 bike). I was thinking of one upping everybody and doing a GX 340 build but then I decided Im not starting my bike with a shoestring. Keep up the good work.
A piece of rope would last longer then a shoestring laff
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
Nice bike Pat! Country roads are always sweet. I gotta stick to my city speeds. Cagers are very unpredictable here. How long is that short chain lasting you?
 

cobrafreak

New Member
Feb 16, 2011
1,049
9
0
sacramento ca
That is just way too cool. I cant believe you guys get away with riding them over there...... im soooooo jealous................ Once again this has been an unbelievable build and your bikie has set the bar a lot higher. Great work
We can't believe you can't get away with riding them over there. Contact your council person and motion to have the law changed.
 
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