Building a Micargi Mustang GTS-Any Tips?

[Cruzin]

Hi,
I bought a Micargi Mustang GTS and thought that it would be a cool bike for a motor kit. I ordered an 80cc kit and am waiting for it's arrival. I know that a few of you have put a motor on this particular bike, and was wondering if you had any tips before I get started? I am thinking that I might want to mount this engine toward the rear of the frame to avoid such a long run of chain. Any input would be greatly appr eciated.

 

[Venice Motor Bikes]

Here ya go...
You're gonna need longer cables, fuel line, a longer engine chain, a few extra links of BMX chain for the pedaling chain & a extra chain tensioner to make your pedaling chain go under the engine.
This bike had 68 spoke wheels which didn't work with the rear sprocket. (I had to switch to a 36 spoke rear wheel.)
You will also have to make the CDI wires longer...

 

[simonjohnwilmer]

Tidy ! , now we need to see someone put a Huasheng/Honda in one of these frames , I have a Mustang but I cant bring myself to go 2 stroke .

 

[Cruzin]

Sounds like a good challange. Any chance of some close up pics of what you did with the chain tensioners. Getting the pedaling chain lower makes a lot of sense. Also did you keep the original grips?
Thanks

 

[Venice Motor Bikes]

Sorry, I can't get any new pics... The bike has gone on to it's new home.
I'm sure you can get the jist of it by looking real close at my pics...
(it now has the kit grips)

 

[momentummotorgroup]

Go for the 80cc. it helps to have the extra power for the weight of the bike..make sure you get all your bearings upgraded, as the Micargi ones are complete crap. I've used them on a quarter of my builds, and every single on I've wound up replacing. I mounted mine towards the rear and cut the manual chain guard with a dremel to make it all fit nice and tight and had to add an extra chain roller on said manual chain side to guide around the slight interference of the engine. I didn't need longer cables with my Grubee 80cc, though I did need a second drive chain piecemealed together until I found an extra long one on eBay, at which point I used a chain breaker and dropped the master link completely. I also would suggest upgrading the hardware that attaches the drive side wheel tensioner to some high grade nuts and bolts, as the ones that come stock strip.

I dremeled out the inside hole of the drive sprocket to fit the 68cc hub and drilled 6 holes total in the sprocket outwards one full measure of the inside sprocket mount plate, and have been running off that without problems for 4 years, barring the blowout of said craptacular Micargi bearings in the rear hub.

I also found the OCC stingray seat is perfect for this bike. Using it makes the physical positioning on the bike a lot more comfortable than the seat it comes with..I had the drive side chain gaurd off for spraying, but it's now reattached and matching the rest of the bike..

 

[bairdco]

does that muffler drag the ground?

 

[momentummotorgroup]

nope. there's about 4 inches of clearance. That muffler is soon to be replaced with an expansion chamber..

 

[Cruzin]

Great help. I like the fact that you retained the manual chain guard and rear fender. The seat works great for the look of this bike. Did you have to push the manual drive chain lower to clear the motor? Also if I understand correctly, you re-drilled the holes in the sprocket to clear the 68 spoke wheel? I know that fitting the sprocket to the 68 spokes would be a challenge. If you have a close up picture of the sprocket, that would be great.
I can't wait to get started. I ordered the 80cc Zoombicycle motor kit.
Thanks for your help.

 

[momentummotorgroup]

I pushed the chain lower using a chain tensioner on the manual pedal side rear wheel armature to give the 1/2" clearance needed.

For the sprocket i literally took the rear mounting plates from the (the rounded ones) from the sprocket and lined them up directly with the holes already cut one width out from the original.. the inside points of the crescent should be touching the outer holes..I then sharpie markered their position and then went in with a metal drill bit on a plug in drill..a drill press woulda been nice but no dice in my apartment.. I wish I had pics to show, but the bike is in storage as it crapped a foot of snow here within the last few days..

the rear fender was cut via dremel+sharpie.. I actually have a rear caliper brake hidden in there.. basically the caliper brake sits where the fender used to attach, then the fender is bolted on through using the same bolt from the brake set. the brake shoes have to be the small length (like an inch size, not the big fat BMX style) or the brake shoes interfere with the chain drive. I wouldn't suggest running this w/o a secondary brake, as the extra long manual chain can pop pretty easily under braking at high speed and then you are riding brake free.. if i had it to do over, i'd have gone with Spookytooth's rear wheel that has the band brake built in and foregone the 68 spokes even though they do look cherry.

 

[momentummotorgroup]

oh. and that rear reflector is actually a generator driven tail light.

 

[NYNEOMITE]

I am the proud owner of the red one. Send me a PM with your email and I will send some close ups during the weekend. Momentum - I would love to see some close ups of yours too. I thought about cutting out the chain guard and putting it back on. I thought it would make too much noise so I just threw it away. I am kind of regretting that right now. Although, it does look really sweet without it.

BTW - I love that seat!! These bikes are the most comfortable ride, that seat could only make it better. Where can I get one?

 

[momentummotorgroup]

If I can wrangle the bike out of the storage unit for my apt and get good lighting, I'll get some pics up on it. I originally had worry about rattling too, but wound up using the 3M padded tape on the motor mount area as well as running along the lip that touches the motor area and it runs rather quietly all in all with the exception on the rear caliper brake. As the fender is attached to the same bolt and with only one point of contact using the rear brake rattles the fender and makes it sound like the motor bicycle equivalent of a semi jake braking. I am going to have to figure out a workaround on this for future builds or again just go with the Spookytooth band brake hub and buy their matching front wheel and then use a front disc brake.

I got my seat on eBay searching for occ schwinn seats for 30 bucks, but have seen them in my local schwinn bike shop as well..and yeah. the seat makes the bike. It was really awkward and unbalanced feeling with the stock seat. Now the dynamics make the sitting position more akin to a standard sized bike, and you have added balance from the way you straddle it in compared to the stock seat..

 

[civlized]

Here is my Micargi Mustang with the front disc brake added. It is currently under construction with a different engine. The engine in this picture is the HS 50cc 4 stroke.

 

[civlized]

Woops! Resized it a little too small didn't I? I'll try to fix that.

 

[civlized]

Sorry about that. You should be able to see this a little better.

 

[simonjohnwilmer]

Seems to fit ok , are you staying four stroke with the new engine? .

 

[civlized]

Oh yeah, I'm sticking with a 4stroke! This is my new engine. I've got it posted in the DIY area.

 

[simonjohnwilmer]

Nice set up .

 

[Big.Dude.666]

GET RID OF THE CHEAP COASTER BRAKE......i broke it with no motor on the bike in the first month...I broke by leg and had my acl replaced...it was not all the brakes fault my friend helped....the brake broke under normal riding..my accident was a few hours after....