99cc Predator Build

GoldenMotor.com

agk

New Member
Oct 2, 2010
151
4
0
Santa Barbara CA
We built this bike for one of our good customers. He went with the 99cc Predator and all of our performance modifications including a custom built header and a custom cam grind. Our customer Craig also added a tach, bicycle gauge which includes a speedometer, water bottle, bike lock, a battery to power license plate lights and several powder coated parts. We used wide rims with Hookworm tires and installed a springer front end with disc brakes.





 

dmb

Active Member
Dec 4, 2010
1,354
3
36
lakewood ca
years ago i saw a 3 yr old girl run up and grab a hot chrome exhaust on a buggy... it happened so fast. i still shutter thinking about that tragic day.
 

agk

New Member
Oct 2, 2010
151
4
0
Santa Barbara CA
I'm just a little curious how much a bike like that costs. It looks great and I bet it runs really good also.
You know what...Craig spent a lot of money on this bike. I don't know what his bottom dollar was all said and done but I think it was close to $3000. He opted to go for several engine mods. The bike would perform great with a fairly stock 99cc Predator but we installed our bored carb, a high flow air filter, a custom built exhaust, we ported and milled the cylinder head and we installed a custom ground cam. Craig also had several parts powder coated. He coated the sprocket, the chain tensioner, the motor plate, the motor plate frame mounts, the cranks and several other miscellaneous pieces. None of our other customers went to that extent. Craig also put up the cash for custom built wheels with wide rims and a cassette for multi speed on the bicycle end of things. We used our jacks haft kit and Craig powder coated the clutch cover/chain guard. We painted black our throttle linkage kit, header braces and several other pieces to give it that midnight black look. We added the battery for the license plate lights which required a mounting bracket welded to the frame. The list of unique stuff goes on and on. Craig was not messing around and knew what he wanted. The result is a motorized bicycle that can climb any hill around here with ease and can exceed 40 mph!
 

DaveM50

New Member
Jun 15, 2014
20
0
0
Minnesota
I have a 1971 Honda CB100. As far as I can tell, the engine is virtually identical to the Predator 99cc except that it has clockwise rotation and an overhead cam. I have to wonder whether any of the parts might be interchangeable, especially things like exhaust pipes/mufflers, etc. The head on the Predator faces the opposite direction from the one on the CB100 when it is mounted, so presumably the head pipe would have to curve differently and the flange might be completely different for all I know. I just know that the stock exhaust on the old CB100 is pretty good and I'd love to be able to add something similar to my ongoing Predator build.

By the way, the CB100 engine (with no governor) puts out a claimed 8 1/2 horsepower. With a good downhill start, I have had it over 60 (manual claims the maximum speed is 52). But I wouldn't care to keep it there for long. 60 on a small bike close to the ground feels faster that 90 on a larger machine. No, I won't tell you how I know.
 

mat_man

New Member
Jan 29, 2011
224
1
0
athens ga
I have to wonder whether any of the parts might be interchangeable
I was reading that the small OHC motorcycles were sold to the 1st world countries
and that OHV ones were sold to 3rd world countries. OHV motors could tolerate dirty oil much better.
I would think that many parts would interchange between these motorcycle motors.
 
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DaveM50

New Member
Jun 15, 2014
20
0
0
Minnesota
That makes sense. Honda still makes a slightly updated version of the CB100 I have (which was sold in the U.S. only between 1970-72). It is available only in Nigeria.

As it happens, a guy from Nigeria lived in the same apartment building as me for a while. He taught me all sorts of interesting things about tweaking and maintaining my old Honda. He also showed me how to carry a passenger, luggage, and a baby on that tiny bike, which he said is commonplace in Nigeria. I don't plan on trying it, but I am amazed at what that little engine can do. Of course, that's running through a five-speed transmission (you get to 3rd while going through an intersection). But I do think the potential of this size engine could be explored much further than it has been

One major difference between the 99cc engine on my old Honda and the Predator is that the Honda engine has some sort of oil pump/strainer arrangement which filters the oil somewhat. There are strainers inside and outside the crankcase--the outside one is to be cleaned each time you change the oil, which is recommended monthly. The Predator has a simple sump, to my knowledge, and only holds 12 ounces of oil (no clutch or transmission built in, as with the Honda). I plan on changing it on the usual "lawn mower schedule" (once every 25 hours of use). Though I am certainly open to suggestions.
 

DaveM50

New Member
Jun 15, 2014
20
0
0
Minnesota
Quite an upgrade! The Honda CB100 weight around 160-170 pounds. With 16 horsepower on tap, you have more power than a Honda Rebel 250 in a lighter bike. Yours must fly!

I've had no complaints with the original engine in my CB-100. It'll run all day at 40-45 MPH, and run quietly besides. Just takes a while to get up to speed. It'll go faster without any problem, but it takes a lot more RPMs to get another 10 MPH.
 

massdrive

New Member
Oct 3, 2013
454
3
0
Las Vegas
Very cool. I've got 2 new predator's boxed and shelved. A 79cc and a 99cc. What are you using for the drive train. I really want to use a CVT on these two builds. Is there a reason why so few are going this route?
 

culvercityclassic

Well-Known Member
Sep 27, 2009
3,115
177
63
Culver City, Ca
I would have to say the hp of the small engine is a factor for not using a cvt. The way to go is a jackshaft setup with a good clutch. Look at the post: Sportsman 80
Check out that setup, I have used it and it works great.
 

massdrive

New Member
Oct 3, 2013
454
3
0
Las Vegas
Yes I thought of the lack of horse power. My plan is to build the stuffing out of the 99cc engine. A jackshaft is used in conjunction with the CVT anyway. This brings up another thought... has anyone used a shift kit with a CVT? I know it isn't needed, but I can't help but wonder.... ya know?