Major mods to an MC-54-150 By jeffdeq (Read 3,031 times)

[jeffdeq]

About a week ago I purchased a 2008 Roketa MC-54-150 scooter that had no engine.



The body was in decent shape and the engine hanger was still in the scooter's frame. Anything else associated with the engine was missing. I had a donor bike and many spare parts that I had to use to get this bike running again. Fortunately the donor bike still had a running engine so I transferred it to this bike. However, this transfer required many modifications. Can you see what they are?

After the first correctly answered posting I will post what was the make of the donor bike.

This was the donor bike.



This is the finished bike.









For a reference, below are photos of a stock bike from Roketa:

[jct842]

Wrong sized wheels

[dragonsparks]

That's what it looks like to me. Are those 16" wheels.
Is the scoot on top a 250 roketa?


Dave

[Cruiser]

Yea, looks like these wheels are larger than stock. The center stand does not mount low enough to hold up the scoot without the addition of spacer blocks. The front disc brake mounts on the opposite side. Front fender had to be remounted (replaced?) probably because of larger wheels and different forks.

Looks nice with the larger wheels and you now have a longer wheelbase. I think it looks better than the original.

[jeffdeq]

Yes, those are 16" wheels. I used an Xingyue ITA YY150T (BMS Pathfinder 150) as a donor bike. The triple tree had identical dimensions in the bearngs and steering stem retainers.

(On a side note, the Roketa MC 54-150 only had 1400 miles on it and had been sitting up for the last 3 years due to engine failure. On the triple tree for the 13" wheel the bottom bearing was packed in grease but the top bearing had no grease. However the top bearing was still useable.)

After installing the 16" triple tree I had to grind back the steering stops about a half inch to allow for more radius in turning. This was a simple bolt in. All work was done with the body off the frame. the speedometer cable was the right length and fit the instrument cluster. The speedometer is reading 50 mph at actual 45 mph.

The engine was a little more difficult to install. A 16" wheel bike has a wider engine case than the standard GY6 engine. It took a 9 1/2" grade 8 bolt to hang the engine to the frame. The carb is a tight fit to remove unless you pull the shocks to allow the frame to lower thus rotating the engine hanger away from the carb.

After I ran the brake lines to the rear I finished servicing the motor, replaced the belt and rollers (using 14 gram) and secured the wiring harness. I then carefully put the body back making all connections secure. When I disassembled the bike I found that there were a lot of missing bolts and screws along with loose bolts. This bike appears to never have been serviced leading to the engine failure.

As for the 16" wheel donor bike, it was a parts bike with many body parts missing. However the engine was still functional so there was no costs for rebuilding it.

All in all, the bike runs good. I have to replace the carb because it has issues for idling properly. The 16" wheels give the bike a smoother ride and the wheel base is 10" longer. The ride is very stable. I really enjoyed test driving it this afternoon. Top speed is 59 mph according to my gps.

Cruiser you are correct, I now have to extend the center stand because I don't think I want to pack around shim blocks, LOL! I also had to re-mark the dipstick for the crank case fot a proper oil level. The geometry of hanging this engine in this frame has the engine at a higher slant.

I have 2 other 16" bikes, a Lance Phoenix 150 and a BMS Pathfinder 200. The Lance has the best ride and engine performance. The BMS is the strongest and fastest at 63 mph but has a horrible, cheap feeling ride.

[dragonsparks]

Kool Rebuild. As I have always sad Were there's a will there's a way. Might not be the Right way or only way.
Ride safe n have fun. Dave

[kalee]

Really nice rebuild jeffdeq, Injoy the ride
kalee

[forcefed44]

I would love to see the pics but the mod pics are inop..

Chris