BD125-2 "Boomcat" - Page 5

oincman · 10-29-2020, 05:25 PM

VM22 carb is too big. The PZ20 is adjustable, just remove the cap over the air/fuel screw right to the left of the idle screw (pry it out). I turned mine out about 1/4 turn and it's running much better and not having the hesitation issue. Ordered jets for it as well. The stock is a 75 or 78 (can't remember).

Got the little thing running pretty good and Belmont Bikes/Venom Motorsports have been extremely responsive about broken parts and are sending replacements.

Drain the forks and replace with 4oz of ATF (in each) and it smoothed out the bouncy front end.

oincman · 11-06-2020, 07:55 AM

To continue the ongoing saga.... The rear swingarm is bent. I can't for the life of me get the wheel centered (and I did true it). Got it as close as I can, but the chain is slack on one revolution and extremely tight on another. Belmont is having another swingarm shipped, but that's gonna take a bit. Gonna add a 14t front sprocket (13 is stock) to try and smooth out the gearing. 1st is practically worthless and will pop the front wheels pretty easily (wife doesn't like it). However, with the 13t, this thing will climb hills pretty easily in 4th and still top out around 50. And I need to find some different rear shocks. No matter the adjustment, this thing is pretty bouncy.

Shmerlin · 12-29-2020, 12:28 AM

Updated review, only 157mi on the bike and I've had several issues with it. Going through the Moto-pro seller, they have advised the factory discontinued the model and that they can not supply parts for it anymore.

cheapermoto · 01-06-2021, 04:40 PM

cheapermoto · 01-16-2021, 10:30 PM

Have changed both front and rear sprockets. Front 17T and rear 35T.

The 35T is the smallest you can go without shortening the chain. Nice improvement and better cruising RPM's. Rear sprocket needed center hole to be machined out by 1/8" or so to fit properly.

I did notice a little lean of the rear wheel to one side after this mod. Not really sure what the cause is. Wheel is on properly with spacers in place etc. Seems like swingarm and or frame might of been tweaked a little from the factory and never noticed before.

Anyone else have any issue with their rear wheel leaning to one side? I'm thinking maybe they are just not that accurate from the factory. Does not seem to be an issue when riding, but may take some measurements to see if I can verify whether or not the swingarm or frame has a bit of twist.

Anyhow, hope this helps others who might be trying to squeeze a little more top end out of this little 125cc. Been having fun with it. These little bikes really take you back to your early days of motorcycle riding. Truly tons of fun.

oincman · 01-18-2021, 08:04 PM

It is what it is. I expected no less and got exactly that. Am I bummed. Nope. Nobody else made one and it's a cool looking retro bike. And it's a wheelie monster for a 125cc with stock gearing.

I'll take it for what it is and try my best to make it better. Worst case, I'm out $1k and change. Still better than a $5k+ Honda that I'd be disillusioned with and pissed at myself for wasting hard earned money on. Who(IMO) doesn't make anything cool, even the Chinese grom clones are better than the Grom.

oincman · 01-18-2021, 08:17 PM

Let me add to this. I'm not a Honda hater. I have two CT90's (which are a hoot). And I think Honda's are a terrific motorcycle. But they are over priced for what your getting and they (Honda) have built a reputation for quality (not innovation, hence the new CRF300L not even having LED lighting) and get away with overpricing.

And I just bought a new Suzuki VanVan (cause I love the styling). And it is in no way shape or form better than the Lifan KPM200 I have (which is actually faster than the VanVan and cost $2K less). Though it can go off road and the KPM can't (which new tires will fix that issue).

I love the Ducati Scramblers, but not the price nor the fat ass weight. I like the Huskvarna Svartilan too, but I'm on the fence about the styling (but I don't mind the $4999 price for a 400cc Dual Sport that'll do 100mph and has Pirelli Scorpian tires).

felixaj · 01-25-2021, 09:50 PM

Yes, my garage is a disaster.

I've been tinkering a bit this winter, but it's too cold to ride in Michigan, so I can't get it tuned in for a few more months.

Upgrades so far:

Removed EGR/Charcoal stuff (not sure what it's called)
-made a block-off plate for the cylinder head port

Knockoff Mikuni VM22 card
-used the stock jets that came with it
-got a thumb screw extension for the fuel/air mix screw
-used the included cone air filter with an angled hose

Semi-knobby tires - links in earlier posts in this thread

Painted the wheels black

Honda CL70 fork boots from eBay

Wire harness for a Battery Tender

Lower handle bars

LED lights - Headlight and rear only
-all lights flashed when LEDs were in the front

Upgraded chain

17 Tooth sprocket in the front

33 Tooth sprocket in the rear

Custom license place bracket

Phone holder

----------------------------------------

I see in one of the photos that I need to adjust the throttle cable at the carb, which I can do by adjusting the nuts at the handle lever. Also, I need to reconnect the carb vent hose and carb bowl drain hose - these both just dangle and should exit below the engine cylinder. The tank vent hose is also just dangling, so I need to secure that down somehow. With this knockoff Mikuni, it starts right up and idles perfectly. With the old one, I could not get it tuned right and would not idle fine until it warmed up, so I would have to constantly give it throttle up and down until it was warm. I'm hoping the carb will give me a little more pickup power to offset the sprockets and I'm not too concerned with going higher than 55mph. I just want it to go 55 at lower RPM's.

If you don't mind tinkering, I think this is a great bike for the money, especially a great first bike. It's not perfect, but I have learned a ton, which I think is worth more than the difference I would spend on a more expensive bike.

Let me know if you want links to anything I used.

China Rider 27 · 01-25-2021, 10:38 PM

Looks cool, cafe racer style. Is that intake stock or did you buy it somewhere? Is the exhaust stock or aftermarket?

felixaj · 01-25-2021, 10:42 PM

Quote:

Originally Posted by China Rider 27

Looks cool, cafe racer style. Is that intake stock or did you buy it somewhere? Is the exhaust stock or aftermarket?

Thank you. The intake manifold "gooseneck" is stock but the carb is a Mikuni VM22 knockoff from Amazon with an angled cone air filter. The exhaust is the stock exhaust that came with the bike.

China Rider 27 · 01-25-2021, 10:53 PM

I agree completely, a great part of the appeal of these inexpensive bikes is the learning and modification that is fun. What is the top speed?

felixaj · 01-25-2021, 10:56 PM

Quote:

Originally Posted by China Rider 27

I agree completely, a great part of the appeal of these inexpensive bikes is the learning and modification that is fun. What is the top speed?

I hit 58 or 59mph, but the RPM's were too high for my comfort. That was before I changed out the 41 tooth rear sprocket with the 33 tooth sprocket. I'm sure it will get much faster but I just wanted to feel more comfortable at 55mph. It's too cold still to test out the new rear sprocket, but I will give an update when it gets warmer outside.

cheapermoto · 01-30-2021, 01:12 PM

Still wringing out the BD125-2. Stock carb 17T front and 35T rear.
Seems to be working out pretty good so far. Will hopefully do a run up to this place called Sugarloaf in the coming weeks. It's a 2000' climb and about a 20 mile round trip. We'll see how the Boom does. For now this was the most recent outing.

Cheers!

Big Bird · 01-30-2021, 02:38 PM

Quote:

Originally Posted by cheapermoto

Still wringing out the BD125-2. Stock carb 17T front and 35T rear.
Seems to be working out pretty good so far. Will hopefully do a run up to this place called Sugarloaf in the coming weeks. It's a 2000' climb and about a 20 mile round trip. We'll see how the Boom does. For now this was the most recent outing.

Cheers!

Funny, I grew up in Bennett Valley, and my mom worked at that state hospital for a bit. So I know the area pretty well. I would be interested how the bike does in Bennett Valley RD, I think it would be a fun ride if it could manage the hills. The boomcat is what got me interested in china bikes again I was excited to know that china bikes were CARB legal and ended up going with a Grom clone due to more parts support. I think the boomcat is a cool little bike and enjoy riding along with you.

cheapermoto · 02-06-2021, 02:56 PM

Are any fellow BD125-2 owners finding any parts support from dealers?

My father has one and needs a few parts. I've reached out to all the places I can think of, but no real success.

Was hoping to find OEM taillight lens and maybe new rear fender, but now starting to think may have to adapt a non OEM part as a solution.

Any help would be awesome.

01-06-2021, 04:40 PM	#64
cheapermoto Join Date: Jan 2021 Posts: 5	BD125-2 Boom Retro 70's Chinese Motorcycle
	2

01-16-2021, 10:30 PM	#65
cheapermoto Join Date: Jan 2021 Posts: 5	changed rear sprocket on BD125-2 Have changed both front and rear sprockets. Front 17T and rear 35T. The 35T is the smallest you can go without shortening the chain. Nice improvement and better cruising RPM's. Rear sprocket needed center hole to be machined out by 1/8" or so to fit properly. I did notice a little lean of the rear wheel to one side after this mod. Not really sure what the cause is. Wheel is on properly with spacers in place etc. Seems like swingarm and or frame might of been tweaked a little from the factory and never noticed before. Anyone else have any issue with their rear wheel leaning to one side? I'm thinking maybe they are just not that accurate from the factory. Does not seem to be an issue when riding, but may take some measurements to see if I can verify whether or not the swingarm or frame has a bit of twist. Anyhow, hope this helps others who might be trying to squeeze a little more top end out of this little 125cc. Been having fun with it. These little bikes really take you back to your early days of motorcycle riding. Truly tons of fun.
	1

01-30-2021, 01:12 PM	#73
cheapermoto Join Date: Jan 2021 Posts: 5	Wine Country ride Boom BD125-2 Still wringing out the BD125-2. Stock carb 17T front and 35T rear. Seems to be working out pretty good so far. Will hopefully do a run up to this place called Sugarloaf in the coming weeks. It's a 2000' climb and about a 20 mile round trip. We'll see how the Boom does. For now this was the most recent outing. Cheers!
	1

02-06-2021, 02:56 PM	#75
cheapermoto Join Date: Jan 2021 Posts: 5	Any parts support on BD125-2? Are any fellow BD125-2 owners finding any parts support from dealers? My father has one and needs a few parts. I've reached out to all the places I can think of, but no real success. Was hoping to find OEM taillight lens and maybe new rear fender, but now starting to think may have to adapt a non OEM part as a solution. Any help would be awesome.
	1

10-29-2020, 05:25 PM	#61
oincman Join Date: Nov 2019 Posts: 99	VM22 carb is too big. The PZ20 is adjustable, just remove the cap over the air/fuel screw right to the left of the idle screw (pry it out). I turned mine out about 1/4 turn and it's running much better and not having the hesitation issue. Ordered jets for it as well. The stock is a 75 or 78 (can't remember). Got the little thing running pretty good and Belmont Bikes/Venom Motorsports have been extremely responsive about broken parts and are sending replacements. Drain the forks and replace with 4oz of ATF (in each) and it smoothed out the bouncy front end.
	2

11-06-2020, 07:55 AM	#62
oincman Join Date: Nov 2019 Posts: 99	To continue the ongoing saga.... The rear swingarm is bent. I can't for the life of me get the wheel centered (and I did true it). Got it as close as I can, but the chain is slack on one revolution and extremely tight on another. Belmont is having another swingarm shipped, but that's gonna take a bit. Gonna add a 14t front sprocket (13 is stock) to try and smooth out the gearing. 1st is practically worthless and will pop the front wheels pretty easily (wife doesn't like it). However, with the 13t, this thing will climb hills pretty easily in 4th and still top out around 50. And I need to find some different rear shocks. No matter the adjustment, this thing is pretty bouncy.
	1

12-29-2020, 12:28 AM	#63
Shmerlin Join Date: Apr 2020 Posts: 18	Updated review, only 157mi on the bike and I've had several issues with it. Going through the Moto-pro seller, they have advised the factory discontinued the model and that they can not supply parts for it anymore.
	1

01-18-2021, 08:04 PM	#66
oincman Join Date: Nov 2019 Posts: 99	It is what it is. I expected no less and got exactly that. Am I bummed. Nope. Nobody else made one and it's a cool looking retro bike. And it's a wheelie monster for a 125cc with stock gearing. I'll take it for what it is and try my best to make it better. Worst case, I'm out $1k and change. Still better than a $5k+ Honda that I'd be disillusioned with and pissed at myself for wasting hard earned money on. Who(IMO) doesn't make anything cool, even the Chinese grom clones are better than the Grom.
	0

01-18-2021, 08:17 PM	#67
oincman Join Date: Nov 2019 Posts: 99	Let me add to this. I'm not a Honda hater. I have two CT90's (which are a hoot). And I think Honda's are a terrific motorcycle. But they are over priced for what your getting and they (Honda) have built a reputation for quality (not innovation, hence the new CRF300L not even having LED lighting) and get away with overpricing. And I just bought a new Suzuki VanVan (cause I love the styling). And it is in no way shape or form better than the Lifan KPM200 I have (which is actually faster than the VanVan and cost $2K less). Though it can go off road and the KPM can't (which new tires will fix that issue). I love the Ducati Scramblers, but not the price nor the fat ass weight. I like the Huskvarna Svartilan too, but I'm on the fence about the styling (but I don't mind the $4999 price for a 400cc Dual Sport that'll do 100mph and has Pirelli Scorpian tires).
	1

01-25-2021, 10:38 PM	#69
China Rider 27 Join Date: Dec 2018 Location: PNW Posts: 982	Looks cool, cafe racer style. Is that intake stock or did you buy it somewhere? Is the exhaust stock or aftermarket?
	0

01-25-2021, 10:53 PM	#71
China Rider 27 Join Date: Dec 2018 Location: PNW Posts: 982	I agree completely, a great part of the appeal of these inexpensive bikes is the learning and modification that is fun. What is the top speed?
	0