Hi.. Are there any engine kits to steer clear of?
- Thread starter Ridem
- Start date
The 72cc 49mm bore labeled as a "100cc" with the round head. The entire engine is a disaster. Horrific casting, the port timing on it is absolutely wild too.
Also the "110cc" (85cc if you're lucky as its never been a 40mm stroke) same issues with the 49mm, both made from the same factory
Also the "110cc" (85cc if you're lucky as its never been a 40mm stroke) same issues with the 49mm, both made from the same factory
You'd be better off asking what companies to use; because the list is much shorter.
I re-read your question and understand it a bit more.
I understand your question better now.
People often justify paying a $100 markup for "better XYZ," falling for the same propaganda companies like CMB have used for years. They claim their products are superior, but the "new features" like 4-bolt tensioners and socket cap hardware are standard now. You’d have to go out of your way to find a kit without those features.
Some claim they recently bought kits with outdated specs like flathead hardware or a 32mm intake, but that's just not true unless they found old stock. Check eBay for the cheapest two-piece cylinder engines—there are only four or five factories left. Avoid Amazon, as brands like IMAYCC or Seeutuk are just generic kits with branded clutch covers.
People insist certain companies, like BikeBerry, offer higher quality, but there's no proof—just subjective claims. When I bought engines, I chose the cheapest two-piece kits on eBay, and I’ve had engines last from 150 to 2,400 miles. Any failures were due to mistakes I made, not product flaws.
Engine #1 - Lasted 150 miles because I setup the clutch so poorly (To readers, how the camshaft rotates onto the bucking bar when the clutch is disengaged, I actually pushed the clutch arm inwards and set it up that way, I didn't know how to fix it so I gave up)
Engine #2 - 1,200 miles (Retired but worked well, wanted to learn how to split a case)
Engine #3 - 2,400 miles (Retired after building an MS440)
I would suggest the kit in the link below. People only like Amazon because if they destroy the engine because they lack basic mechanic and tool understanding they can return it.
For Motorized Bicycle Silver 80cc 2Stroke Cycle Bike Engine Motor Petrol Gas Kit | eBay
<li> Description: This is a High Quality Aftermarket Parts This product has undergone rigorous quality testing Durable and easy to install and replace The most cost-effective and best after-sales service Quality assurance that gives you peace of mind</li> <li> </li> <li>Description: This 80cc...
www.ebay.com
Pexmor is one brand I know to steer clear of. It's the type. Emcee is referring to. For "100cc" I went with a yd bottom end and the ld cylinder and head with a hand made 4° offset woodruff key set back to smooth out the motor. As yd bottom ends are notoriously advanced in timing.
Wow.. Great info. Thank you for taking the time to punch that out. At first glance it's very confusing. Especially because customer service is a thing of the past almost. Then I saw one site selling engines for less than a hundred, but over five hundred for delivery. Hard to believe that people are so daft these days, that they would buy a deal like that.I re-read your question and understand it a bit more.
I understand your question better now.
People often justify paying a $100 markup for "better XYZ," falling for the same propaganda companies like CMB have used for years. They claim their products are superior, but the "new features" like 4-bolt tensioners and socket cap hardware are standard now. You’d have to go out of your way to find a kit without those features.
Some claim they recently bought kits with outdated specs like flathead hardware or a 32mm intake, but that's just not true unless they found old stock. Check eBay for the cheapest two-piece cylinder engines—there are only four or five factories left. Avoid Amazon, as brands like IMAYCC or Seeutuk are just generic kits with branded clutch covers.
People insist certain companies, like BikeBerry, offer higher quality, but there's no proof—just subjective claims. When I bought engines, I chose the cheapest two-piece kits on eBay, and I’ve had engines last from 150 to 2,400 miles. Any failures were due to mistakes I made, not product flaws.
Engine #1 - Lasted 150 miles because I setup the clutch so poorly (To readers, how the camshaft rotates onto the bucking bar when the clutch is disengaged, I actually pushed the clutch arm inwards and set it up that way, I didn't know how to fix it so I gave up)
Engine #2 - 1,200 miles (Retired but worked well, wanted to learn how to split a case)
Engine #3 - 2,400 miles (Retired after building an MS440)
I would suggest the kit in the link below. People only like Amazon because if they destroy the engine because they lack basic mechanic and tool understanding they can return it.
For Motorized Bicycle Silver 80cc 2Stroke Cycle Bike Engine Motor Petrol Gas Kit | eBay
<li> Description: This is a High Quality Aftermarket Parts This product has undergone rigorous quality testing Durable and easy to install and replace The most cost-effective and best after-sales service Quality assurance that gives you peace of mind</li> <li> </li> <li>Description: This 80cc...www.ebay.com
It has been a long time but I have delt through ebay many times without problems. Recently tried to buy some saw parts from Amazon. Swore that I would never buy anything through them ever again, unless it was something that I didn't need. Haha. Hard to figure how they became so popular. Ebay was ten times more functional on their first day in business, about 25, maybe 30 years ago.
Glad I decided to ask some questions. : )
Yep, I can see that's true already. Cheers.
Thank you. It would be interesting to see how you did the off set key. I've heard from a few people, that those engines shake their bikes apart. But I havent seen anybody using rubber mounts yet. Not on the internet or otherwise. I see a lot of posts for blown coils, but no mention of installing ground straps to remedy.
If you search woodruff key on this site you can see the key I cut.
Hey, definitely stay away from those cheap Chinese kits from the marketplace. They may look the same but quality varies big time. You're only saving on paper. From my experience BBR Tuning kits have a solid reputation especially for durability. I also tried a Zeda kit and it only lasted a month. Trust me it's worth spending a bit more 
I would suggest this ATM https://www.ebay.com/itm/133208897389?_skw=wild+cat+bicycle+motor&itmmeta=01JB9C42PGXYWYN0BD3XGW7EYG&hash=item1f03de776d:g:TbkAAOSwnSJdnoDf&itmprp=enc:AQAJAAAA8HoV3kP08IDx+KZ9MfhVJKm+NCo/LXDgEx6KHUlN1iW512XDEs39rhuwooCvlmnADbrt/IhZgigpHSiinE6o+cW87zGcLfkuwGxh4vLO5ixKJG3rWonBp1RCPFkjwmjCKKoQ7mvPUBa/Qpg4YFhe1juNMYOAkKuN7PFKAyPjQyYBy+QRhh1fYhTiu8jf/NVfxMcpi+u2h5VGXeeo8n9u9umdjkAMjY4myBrfzRXXbTHe6y5p0bKMTCvXVnLoAubQqgJHgdRJJGRnRYHOjuc5PylM604v2D7ZRu4XO/2l7UPUzQwBfm35yc0dREHMZA7mIg==|tkp:BFBMqquQrNpk
It's ported and reeded with windowed piston and has a balanced crank. It's worth it at $179.00
It's ported and reeded with windowed piston and has a balanced crank. It's worth it at $179.00
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Bicycle-engines.com has a 6 month warranty. I like doing business with them. I have heard good and bad of the 49mm iron bore from eBay. I hear they have potential soft seize issues, and to improve the port timing just use a Dremel and match the sleeve to the ports. BBR has decent engines, but don't fall for the "stage 4 racing" crap. I personally love my phantom 85, but that's not an engine for someone just getting into this hobby.
Nice.. That sounds very good to me, especially Japanese bearings. Never know what kind of metal the Chinese will use. : / I have three possible mounts, I'll post some photos and specs as soon as I can. Maybe you can help me come to some conclusions on mounting. Thank you..
Sure I don't mind but I would suggest the bank of knowledge this site has to offer...much better ideas .
I made my own version of this with an old hub adapter so I had a bolt hole for an exhaust hanger...
