New Bullet Train BT Build Coming!

[dparham]

true! it looks like some head work is possible or at least like you said... maybe even top end be used with current heads and jugs or something comparable... would be nice to see how far this thing could go... from what I can tell and from the pics it does look to all be higher grade than the stock 66/80cc kits we know and love lol my current build is brakeless so waiting on some parts to give it a front disk brake.. the back is that HD freewheel setup I got few years ago and built it up on a huffy frame... its a really wide axle and the frame was not designed for that so I had to do some "adjustments " to widen the dropouts and then shim the pulleys so Id get chain alignment.. then dished wheel slightly it has a nice feel... especially with those big tires ... on this new engine I want to take a little a port timing as it currently is and if any need to adjust that would add anything to it being its rating already from the manual at 5hp .. also an expansion chamber and updated intake and carb ect... this is current build... the drum brake isn't working properly at all yet... and front brakes were a joke using these... so I'm going to disk lol was scary on first ride and it took off with basically flinstone brakes lol

 

[dparham]

That makes me think though, seems as though they spray paint the engines assembled to give them a uniform silver color, I wonder if case parts if ordered alone will have this paint on them. I also really wonder why they paint them at all when it's not that big of a change in looks.

well.. aluminum will corrode and this is probably just a protective coating... they won't take the time to polish it up and make it look nice so a little paint can help here lol I too would rather no paint and paint myself but maybe sitting on those ships for months in damp conditions they feel its best to have some protective layer... it is a nice finish on the BT90 however compared to what Ive seen on the standard engines... I had one 10 years ago that looked terrible but it ran like a scalded dog and it ran out about 13k miles before blowing engine up... I built a second one faster and gave the first to a friend and he drove it to death not knowing fully how to maintain it.. and still made it about 13k... he did check head bolts and was diligent about mixtures... back then jut didn't know how damaged and ended up giving the parts away to a kid who said he could fix and use for work...

 

[Frankenstein]

I suppose if they want to protect it from that weird white oxidation that forms on s**tty aluminum then painting is a good idea, otherwise corrosion is a minimal problem on aluminum it just forms an oxide layer and that protects it for the most part. I'm surprised they didn't go ahead and paint a bunch black, that's a pretty common color on the China girl. I almost want to go and paint mine black just because, I think it will fit in well with the concept I'm still working out, have lots of flex pipe so I'm going to stick to pretty much stock exhaust and make some long large flex pipe out to be the exhaust, I always liked that big pipe look and I think it will sound pretty cool too. Think of how a whizzer flex pipe looks and increase that to a 2 inch diameter. Found the stuff at an advance auto store up the way, just happens to fit snugly around the slightly larger diameter (compared to normal 66 stock muffler baffle tubes) bt stock exhaust. While I'd like to bring the beast out and use an expansion chamber I want to let this motor die a normal death so I can start to see where and what needs improvement at the lowest end of the scale.

I have a feeling most of the electrical components (including that starter and reduction box that's part of it) are plain out cheap substitutes for parts you'd find on major brands, the relay looks the cheesiest and I think it will be one of the first parts to take a dive, I haven't clicked it shut yet to measure known loads across it but I remember many of the screwy cheap ones either started to fail closing the circuit or for whatever reason had unusually high resistance across the shutter which can put unnecessary load on the battery while trying to start. Some just overheated and made that magic smoke, never to close the circuit but still clicked shut, leading me to think I had other electrical issues. I think a good Honda oem part could replace that, and most of the other parts probably have Honda or Yamaha oem compatible components that would probably outlast such a small engine.

The manual says 5 hp but I don't take that with a grain of salt, I'm sorry but I just can't, the design is heavier and the crankshaft spins more weight with a clutch and a flywheel but the cylinder is a mear 4cc larger, you are lucky to see 2 hp from a stock China girl, which come to think of it they have a bad habit of advertising as 5 hp as well.

Me thinks they somehow got the kw to hp math messed up with the kilos to pounds math... Silly Chinese people we know your tricks.

 

[dparham]

hahaha yup... I was looking at an upgrade for a GT90 kit at BB and they said u to 10HP!! holy canolie! but I agree.. even though I'm so used to seeing old parts and making them work the clean electrical box was tidy.. maybe its been upgraded... I'll send pics.. Im not really super familiar with Chinese electronics lol well except iPhone lol

 

[Frankenstein]

hahaha yup... I was looking at an upgrade for a GT90 kit at BB and they said u to 10HP!! holy canolie! but I agree.. even though I'm so used to seeing old parts and making them work the clean electrical box was tidy.. maybe its been upgraded... I'll send pics.. Im not really super familiar with Chinese electronics lol well except iPhone lol

IPhone is a Chinese product designed in the USA, they also tried not to screw people over too much either so they got that going for them.

The box looks perfectly fine other than being a bit oversized IMO, it's the actual components that just look like 90% of the similar parts you'll see on eBay for less than 2 dollars a piece. Mind you the oem equivalents that major brands will sport will be in the 15-25 dollar range, but those are parts that last 5 or 6 years on a quad or dirt bike, that being said there's an actual reason they cost more, it's just because they are simply better quality and have better qc from the factory because the major brands want to cut down on returns and establish a reputable name, the no name brand relies on selling 10 times the amount and hopes 80% of the crap shots never come back, which at their price they rarely do.

 

[dparham]

yup lol

 

[KCvale]

I built one of the first to get to the US to do a Review.
This may help some
http://kcsbikes.com/topic.asp?TOPIC_ID=948

Enjoy it before any way to start it fails.

 

[dparham]

KC do you have yours running yet again? how old is your BT80? I was reading there were some changes and updates.. not sure what they are though

 

[Frankenstein]

KC do you have yours running yet again? how old is your BT80? I was reading there were some changes and updates.. not sure what they are though

No he doesn't and doesn't plan to run it, I honestly wonder why others are having no problems while kc did, I would also call BS on the "changes and improvements" when they haven't even sold them yet to find the faults, I kind of think they are saying improvements over the China girl if anything.

 

[dparham]

yeah maybe... ill have to look at it again when im home to see how it was worded... it could just be " advertising terms" lol