Boy go fast/engine

Skyliner70cc

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Note: After posting this, I went online and noticed that this vendor now sells engines with the locking clutch lever, roller wrist pin bearing, and bearing wheel tensioner. If clutch and paint issues are improved then my review may no longer be applicable. Please submit your experience with these engines!

I've had the opportunity to purchase two of his engines over the last 3 months.

Here are my general observations:

1. Quick shipping is a plus.
2. First engine was not properly packed and the plastic throttle assembly was (crushed) damaged. Vendor replaced it reluctantly but said he normally requires buyers to file a claim with the shipping company. Shipping company would not have honored the claim if I had. The box was not damaged on the outside.
3. Cheap older style clutch assembly. Yuk! These types NEVER work on amy of my bikes. They can't be depressed sufficiently to lock on my Skyliners or Searcher bikes.
4. Both engines start easily and are VERY smooth. Much less vibration than my older Dax engines. My only comment regarding the engine is that the engine is very sensitive to the choke setting and requires some fiddling with the choke while starting to get it to fire up. I drilled out the hole on the choke plate and opened up the airflow going into the engine. This solved the problem and engine now starts easily on full choke.

5. Clutch: BAD. Unlike Dax engines, the clutch cannot be adjusted properly. To this day, I cannot find an appropriate setting on the cable that allows me to have the clutch engage completely when released and NOT spin the wheel when it is locked into place. I have never had this issue with Dax or Kings motorbike engines. Also, the clutch setting seems to be tempermental and dependent on temperature. On colder days, releasing the clutch lever does not allow 100% positive engagement and clutch slips when starting. On warmer days the opposite is true and locking clutch does not completely allow disengagement. This is a deal breaker for me and the 75 bucks I saved in buying these engines is not worth it in my opinion.

6. Power: First engine power came on quickly with my normal break in procedure and was pulling 25 up hill on a 50 tooth sprocket. Second engine can only muster 17 mph. I'll let you know if things change.

7. Paint: Probably the worst paint quality I have seen in the almost 50 Happy time kits I've purchased over the past several years. If you value a decent paint job on your tank and chain guard, look elsewhere.

Overall comments: Value is offset by the clutch issue, need to buy locking clutch and a true roller bearing chain tensioner and lousy paint job. You get what you pay for.
 
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Say what you want about Boygofast, you get what you pay for...these kits are NOT for clueless people with no mechanical aptitude.

That being said, I've had my 80cc running for about 3 weeks now, and it's the most fun I've ever gotten out of $175 in my whole life!! The first and only time I forgot to shutoff the fuel valve I walked away from my bike for 20 minutes and came back to a giant puddle on the ground and an empty tank...oh well, won't do that again (I'm guessing the carb tickler stuck open, it leaks a bit).

If you need something that's totally reliable and comes with a real live person to hold your hand and talk you through an install then you should probably save up another $400 dollars and buy the cheapest GEBE...

Personally I'd rather buy 4 HT engines for the same price, I hear Boygofast has been known to work bulk discounts :)
 
yes I agree...

in fact, I have found with many chinese products, a little mechanical aptitude goes a long way.....

if theres one thing I dislike about this 80 cc boygofats engine, its that it doesnt have any real power to go up my mountanous roads....it seems when starting from a complete stop at the botton of a 25 + degree sloped road , the engine cannot buuld up enough rpms to climb the slope.......Im not sure if changing the back sprocket is gonna be enough to change this....because it seems like a rpm problem when starting from a dead stop.....

20 mph is plenty fast for me on the top end...but now I have tpo figure out how to make the bottom range and midrange power strong enough for the hilly roads in my area.
 
I used to have a older honda 50 c.c 2 stroke motorcyle and I remember that motor having plenty of power...

since this boygofast engine is a 69 cc 2 stroke, and has virtually no low end/ mid range power, that shows that theyr may not be constructed as intellgiently to handle multiple driving condtions
 
Boy go fast engine Clutch Issue

I just got my engine and I am attempting to do a build. I am having what seems to be a problem with the clutch. When I push the clutch bar all the way to the engaged position, I cannot turn the chain sprocket by hand (no chain on it). Am I suppose to be able to turn the sprocket by hand when the clutch is engaged? I am trying to thread the chain onto the sprocket but if the sprocket won't move, the chain cannot be put on. Hopefully I didn't throw good money down a rat hole by purchasing this engine.

Thanks.
 
My sprocket seemed to be stuck too when I was trying to thread the chain, I had to hold the clutch lever down then pry on the sprocket a bit with a screwdriver, but as soon as it started to move I never had another problem with it.

Or you could try taking the clutch cover off (opposite side from chain sprocket) take the screw out, then unscrew the STAR nut, pull the clutch plate off and then try work the sprocket loose...probably a good idea to do this anyway, just to make sure things look ok in there. Put a pea sized bit of grease on the little gear and cut yourself a cardboard "silencer" for the inside of the clutch cover too while you're in there.
 
I just got my engine and I am attempting to do a build. I am having what seems to be a problem with the clutch. When I push the clutch bar all the way to the engaged position, I cannot turn the chain sprocket by hand (no chain on it). Am I suppose to be able to turn the sprocket by hand when the clutch is engaged? I am trying to thread the chain onto the sprocket but if the sprocket won't move, the chain cannot be put on. Hopefully I didn't throw good money down a rat hole by purchasing this engine.

Thanks.

You wont be able to turn the sprocket by hand. Use the socket that came with your kit.....
 
just a reminder...this started as a consumer review & we can't let it become a clutch-repair topic. if there's nothing on the subject already, then please start a topic about it...this is how the "tech manual" grows...with everyone's help :)
we're getting way too tech/mech here. find the proper forum here----> http://www.motoredbikes.com/forumdisplay.php?f=68

now, let's get back on topic.... what was it, again? Smuggling? :rolleyes:

Note: After posting this, I went online and noticed that this vendor now sells engines with the locking clutch lever, roller wrist pin bearing, and bearing wheel tensioner. If clutch and paint issues are improved then my review may no longer be applicable. Please submit your experience with these engines!
 
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