Grubee SkyHawk 80cc Black Bicycle Engine Motor Kit EPA Certified

Fun to ride when you finally get it assembled...Took me days to get this thing road ready, not 6 hours as some claim. I can see it taking "only" 6 hours if you have lots of spare parts and have worked with every known frame style, cause mechanical skills will not be the only thing you need and I will brag a bit, I have plenty of mechanical skills with tools and I did not find this to be an easy task, but even then it was more time consuming due to needing to take breaks from so much frustration.First thing to break during assembly was one of the carburetor flanges that goes to the intake side and Kings Motorbikes has yet to respond to my email. The carb breaking was one of two major issues I ran into, second being the chain binding. As far as the carb went, here are for finger like tangs and the top one broke clean off leaving a nasty gap between the carb and intake pipe. Once I found a way to work around it, the carb still refused to supply gas, but that turned out to be a poor quality intake gasket sucking tons of air in. I added an additional gasket to the existing one and it finally runs on it own (and can be riden now).Clutch will vibrate your teeth apart as well as the chain causing alignment issues. I had to add my own lower chain guide and added one just behind the engine so the chain will not fall off the engine sprocket and get bound inside the sprocket cover. I had heck of a time unjamming it, but the upside was, I was able to pedal home. This was with the front and back sprockets aligned up pretty decent, granted, not perfectly on my particular frame.BTW, if planing to put this on an aluminum frame or oval lower frame bar, it will be a pain! Best suited for rouned frame piping work, but you can still get it to fit with additional hardware and hacking up the air filter housing to cram it into the frame, worked for me :0)If the price was any higher, I'd be pretty unhappy with the kit, but now that I have it going, I am in a bit better mood.Don't trust the bolts, washers or nuts, they are very LOW quality. I am upgrading to Stainless steel and #8's. High stress areas like the motor mounts, intake and exhaust, use #8 bolts. For covers, Stailess steel hex will add a nice touch and also last a whole lot long without stripping out. If you plan to use any sort of lock tight, don't use anything more then the blue, the red is way to strong and is simply not needed. Lots of good sites to help us all out when needed. The chain tensioner in this kit has the worst bolts possible. I stripped the main 2 that clamps it ot the frame right away. I have since put on a differnt and much nicer looking set up to keep the chain at bay.Warning! warn your mate ahead of time that you will be using every 4-8 letter cuss word ever made in the history of human kind, also, you might make up some new ones cause for some of us, you might not get a kit so forgiving like I was unfortunate to get. Sure I got mine going, but it cost me my wife, kids, dog and 86'd out of the hardware store.....ok, not quiet that bad, lol.

It has no return policy. Don't buy, if it is street illegal in your state.

I started off with a 4-stroke engine which threw keys every time I attempted to engage the clutch to ride. Because of this...I ended up buying one of these 66 cc kits. Having experience...as well as reading everything on several forums on motorized bikes...took about 8 hours to put together. Half of this time was spent taking off the 4-stroke engine...because I will put it back on in the future once I can afford to get a belt drive.The biggest problem with the kit I used was the magneto/CDI wiring. Having a friend help me who had built another kit about 2 months earlier...he & the directions were unclear on the correct wiring...so we fried the electrical system. Will by buying another magneto/CDI this week & be back on the road late this week or early next week.For those of you worried about the 66 cc engine...don't be. While many states require 50 or less cc...as long as you take off all stickers/plates saying the size of the engine & ride safely...you will not be bothered. As with anything where you draw attention to yourself...you will get that attention when you don't want it.If you need any questions answered...feel free to join some of the forums available to you. To find these...put motorized bicycle into your favorite search engine. Have all ready gotten the correct wiring sequence on the electrical system...as well as other information you will want/need to get the most out of this hobby. All of you who did this without the help of others who have come before you...means you didn't need all of the stress & bad ratings you have given these engine kits. I & others are more than happy to help you if you will only ask.

These things are great, I've built 3.These engines require quite a bit of oil to run reliably without a ton of heat.I have only stuck with the Grubee Skyhawk Brand.I've built one in 4 hours without issue, replacement parts are cheap/affordable.Aftermarket support is great. I 100% support the use of an expansion chamber exhaust.I've purchased the jackshaft transmission for my own bike which is costly but nice to have because it make the engine a 7 speed.they do have a short break in period, stock components will get you to 35km/h easy, mine with expansion chamber upgraded carb, and head will achieve 62km/hAs fun to work on as it is to drive.

I have used this engine kit to power my diamondback beach cruiser for a year. The engine is actually rated at 2.8 HP new although most experts say the power will go up to about 3.5 after breaking in. It will get my heavy (280 lb) body to about 25mph. Still need to pedal up hills but not too difficult. Engine is quiet. Idling along the engine is inaudible at distances greater than 50 feet. Full throttle it is still very quiet compared to a lawn tool.Price is way out of line. Wholesale price from China is less than $50US. They retail around $99-130 online from other sellers.The chain in the kit is not very good. You will need to upgrade to a 550 chain sold at most motorcycle shops and farm hardware stores.You will need to use thread lock liberally on the bolt threads. Not included with the kit but recommended in the manual.The method of mounting the sprocket to the era axle leaves room for problems. Mine was impossible to align perfectly. Had the chain derail as a result, bending the rim. There is a solid axle rim and tire designed for this kit. Save yourself the headache and get it.With proper care this engine can get you about 15-20,000 miles. Invest in good tires and a good bicycle drum brake also and it will give you reliable service.

The Kit was quite easy to assemble, the hardest part was adjusting it to fit the frame and adjusting the chain which is still very easy to do. It works great, and only goes about 25mph with my 250lb rear on it. Runs like like a champ though, I'm still on the break-in gallon of gas though.