Malossi BBK for People 50 2T

[chaz35]

I've had the kit for awhile (Malossi 319987 bought on sale), finally getting around to installing it.  I have been stalling because of concerns about several issues like getting the wrist pin circlip off the piston, chamfering the ports in the cylinder, and working on the engine while still in the scooter.  I now have another scooter running I can ride, so can take my time installing the kit, if I run into trouble.

Ideally, would remove the whole engine to work on, but appears a lot of work, so my plan is to just take off enough plastic to get to the engine.  Plastic came off easy.  This is 2nd time I have taken plastic off this scooter, so I am getting better at it.  I took off the seat and bucket, then the 2 side panels came off together.  Just 2 screws on the front, 2 nuts on the back, disconnect the wiring for the lights, and it all comes off.  Looks like enough room to access the engine OK now.  Then, I removed the pipe (already have Tecnigas Next-R pipe) and blower housing, all that came off easy.  Next, pull the head bolts, remove the head and cylinder.  The cylinder was stuck, so I used a rubber mallet to knock it loose, and slipped it off, exposing the piston/ rod.

Now the hard part, as I suspected the pesky little circlips are difficult to get off and you don't have the room to get at them easily.  I tried needle nose pliers 1st, but my pair wasn't up to the job.  So, then I popped it out with a small flat screwdriver.  I did everything wrong:  no safety glasses and didn't use anything to cover the open crankcase, so of course the circlip went flying.  I was lucky didn't hit my eye, and haven't found it yet.  I am hoping it's not in the crankcase, could be there, but probably not.  Just have to remove circlip on one side, then push out the wrist pin and remove the piston.  I worked on the scooter on the driveway, not smart, so I covered up the engine best I could and went inside to look at the new kit.

I will stop now for a break, will post more later.  Cheers

[chaz35]

OK, have engine installed complete on scooter, but going to take back apart to check it over some.  I want to take some measurements, like ring gap, and piston to cylinder clearance and compare with the OEM parts.  Want to look for missing circlip in crankcase, chamfer the ports, and look at bottom of the piston where rod connects to wrist pin (just curious, seems like too much slop side to side, but I am sure OK?).

I searched the web for "dropped circlip into crankcase" and got a few threads on what to do.  Was interesting reading, seems like common misstake, got some good ideas, how to avoid this problem next time.  Also, searched for magnets to retrieve the circlip if it's in the crankcase.  There are some really nice magnets out there for not much $'s, may buy one.  Also, order a nice pair of needle nose pliers.

I did some research on chamfering the ports and decided to get a flex-hone.  I saw several posts where people used them with good results.  I am familiar with flex-hone, have used them many times to crosshatch cylinders for 4 cycle kart engines.  Basically, takes approx 30 seconds to do the job, and don't have to worry about messing up your cylinder.  I ordered 1 7/8" 240 grit alum oxide flex-hone, costs approx $30 shipped.

All for now, working on 05 Super 9, installed Tecnigas Next-R pipe, runs nice, but now need to tune CVT.  Cheers

http://www.amazon.com/dp/B002YKNOLQ/ref=wl_it_dp_o_pC_S_ttl?_encoding=UTF8&colid=2F4U9IFCVIJRU&coliid=I3G4XTL020VASF

http://www.amazon.com/gp/product/B000X4MOZM?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

http://www.amazon.com/gp/product/B00455PJ7K?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00

[chaz35]

Disaster strikes!  Got it all back together, started up, and could tell was going to be awesome.  Took it for some slow riding, remember recommended 500 mile easy break-end.  Was running fine, then started acting up, like carb problem, was hearing some noises I never heard before, was getting hot, so I headed for the house, only rode it less than 10 miles.

I pulled the pipe and piston didn't look good, looked dry, so I pulled the cylinder.  Actually, didn't look as bad as I thought it would, but a lot of grime everywhere.  No real scoring, rings were loose, everything looked OK, but dirty and worn.  Nice tight rod is not nice and tight anymore.  Ring gape went from .008" to 1/16".  Basically, most likely I was an idiot and didn't clean cylinder enough after honing it with the flex-hone.  I think in less than 10 miles I put 25,000 miles on my engine.  I don't know what else it could have been unless the Malossi kit was defective, not likely?

Engine probably needs total rebuild at this point, which I don't think I am capable of, especially after this experience.  Only idea I have is to pull the engine off the scooter, flush out the case, put it all back together, and see if it will run.

Will be looking for another People 50 2T to try again, think could probably be successful with BBK 2nd time, I learned a lot.  I am OK, have messed up stuff in the past and survived, so I am not too worried about it.  Sure was a nice running scooter even as 49cc, but that's gone now.  :-(

[chaz35]

Did a little more research on cleaning cylinder after using Flex-Hone.  I read instructions, but didn't follow them.  Supposed to use 10w30 oil.  Flex-Hone makes honing oil they recommend, but don't have to use it.  Specifically, do not use solvents, like diesel oil,  Of course, I used diesel oil.

Apparently, solvents make it harder to remove all the grit after honing, and you don't want to use solvents to clean with either.  Hot water and detergent is the recommended way to clean.  Actually, I used hot soapy water to clean, which I never used to do, so I had false sense of security I guess.  However, hot soapy water apparently works well for oil, but not solvents, like diesel oil.  The purpose of the oil is to suspend the grit in the oil, so it comes out when you wash with hot soapy water.  Apparently, the solvents are bad about burying the grit in the metal, making it harder to remove.

I always used diesel to hone with and clean up 4 strokes with good results.  Usually would blow off with compressed air, wipe down with clean cloth to get most of the diesel off, and then hose it off with the water under pressure.  These were racing engines, and would run a little faster if loose anyway, so a little grit after rebuilding was OK.  I would change oil after every run, so any impurities got flushed out.  2 cycles are definitely different in that regard, I know that now.

Found another People 50 2T already, but 500 miles round trip to get it, probably too far for now.  I am beginning to warm up to rebuilding the engine.  Cheers

[chaz35]

Found cycle shop that can split case, so decided to pull engine, clean it up, and possibly have them evaluate it.  Actually, looking better to me now, have better attitude about it.  Latest issue, wrist pin is stuck in the piston, oh well.  Cheers

[chaz35]

pic of engine

[chaz35]

I am thinking about buying the stator puller, appears can get for less than $20 shipped.  The tool to split the case and pull the crankshaft are pretty expensive, probably another $200 for both tools, so cheaper to take to shop that already has the proper tools.

I need to verify the stator puller is 24mmx1mm external right hand threads.  Anyone know?

http://www.amazon.com/dp/B005CWA07O/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=2F4U9IFCVIJRU&coliid=I1B0PH8CYWWP88

[chaz35]

My thinking now is, if can pull the crankshaft seals, can probably clean out the crankcase fairly well without splitting the case.  Then, assemble with new piston rings, and see how it runs?  So, need a stator puller to get to that side crank seal.  I think I can pull the seal out with a dry wall screw, anyway had this same idea, then 1st youtube vid I watched used same method to pull seals on old Yamaha 2 cycle engine, that was cool.

If it has problems and needs new crankshaft, not really any worse off than before, except a lot of hours working on it.  Cheers

[chaz35]

Be careful to hold handle bar with one hand and back of scooter with the other, when you pickup the scooter to remove the engine.  I made the mistake of holding with both hands on the back, the handle bars turned, and the scooter dropped on it's side.  With both hands on the back, you don't have any leverage to keep it upright, I quickly found out, so now have bent left brake lever.  With one hand on the handle bars to control and one hand on the back to lift, it's easy to move scooter around.  Cheers

[chaz35]

I ordered stator puller, 24mm x 1mm external right hand threads.  I was able to verify 24mm and right hand threads.  When it comes in, I plan to pull the stator, pull the crankshaft seals on both sides, and try to clean out the crankcase best I can.  Then, put it all back together and see how it runs.  Worst case, I have to disassemble it all over again the rebuild with new parts.

[chaz35]

Got piston pulled.  My new needle nose pliers work great, pulled out cir-clips on both sides no problem, very nice to have right tool for the job.  Wrist pin stuck, but I made a nifty wrist pin puller out of a block of wood, long bolt, and couple of other items I had laying around, cost $0, worked great.  Rod small end needle bearings looked bad until I cleaned them up a little, then looked acceptable, most of the slop went away from rod big end to piston.

I remeasured piston to cylinder clearance and about the same as before running engine.  Appears bottom of piston has a little larger OD than top of piston, approx .006" on bottom compared to .008 to .009" on the top.  I measured to OEM piston/ cylinder clearance after approx 7500k's and it was approx .003" on the bottom compared to approx .006" on the top.  The OEM piston/ clylinder was amazing, had very little wear on the cylinder and probably no wear on the piston.  Only issue was some carbon, probably from previous owner running cheap oil.  Things are looking up, maybe not so bad after all.

Still waiting on stator puller I ordered.  Probably will start cleaning crankcase inside, maybe won't have to pull crank seals.  When you rotate the crankshaft, feels gritty now, so know is dirty with flex-hone grit.  Next, I am going to flush it out with water from the hose and diesel fuel.  Cheers

[chaz35]

Cleaned out the crankcase with diesel, dish detergent and water, compressed air, and light coat of diesel over everything.  Seemed clean, but will still probably pull crank seals and clean again, just to be sure.  I don't think need to split the case unless something is worn out and needs to be replaced, and so far all is looking OK.

I have old Dremel and tested it some to see if would work to chamfer the ports.  I don't have the proper carbide burrs, so did a lot of looking on web for what to get.  There are some really cool air micro die grinders I considered.  For around $50 could get micro die grinder and set of carbide burrs that would probably work great.  Only problem, my air compressor is rated 2.7 cfm at 90psi and the micro grinders use 4 cfm.  Probably would work OK, my compressor has 2.5 gallon tank and 150psi max, so would probably run for awhile before running low on air pressure?  These micro grinders take 1/8" bits and turn 56000 revs, so if you did a lot of work, would be better than Dremel.

With the Dremel, I probably need Carbide Burrs with 3" shaft, which are hard to find, and expensive.  I maybe got lucky and found a really good brand on ebay with 3" shaft, double cut, 9 degree angle, that may work really well for $6.35 shipped.  We will see.

Next, I need to order some gaskets, seals, piston rings, prepare the piston/ cylinder, and put it all back together.  I will be lucky if I get it running before it gets cold.  It's already getting cold for night riding.  Cheers

[chaz35]

Got my 3" shaft carbide burr in and used it with Dremel to chamfer the ports a little.  I practiced on the OEM 49cc cylinder removing some carbon and chamfering the ports too.  Works pretty well, but can't run max revs or wobbles too much.  I think burr is straight, think my Dremel is worn.

Waiting for some parts, then can finish it up.  Unfortunately, based upon past experience, will probably be another month before I get everything in.  Fortunately, my two Super 9's are running like champs, went on long ride on 05 Super 9 today, it was flying.  Cheers

[chaz35]

Hopefully have all parts to finish putting back together.  Weather is wet and cold here, but supposed to get nice in a couple of days, so looking forward to working on it.  1st up, pull the crank seals and make sure the crank bearings are clean.

I noticed Malossi has final drive kit for People 50 2T part number 6711055, anybody install?

[Triesandluth]

Finally looked up your thread.  Glad you got it straight.  When I did my bbk,  I just used a cheap precision file set to knock the edge off the ports.  I know easy more now about porting,  gotta be careful not to change too much or you'll end up with possibly bad results.  I'm about to port my tgb cylinder.  If that turns out well I will try my luck on my other malossi cylinder for my super 9. I've been learning a lot at the other forum. 
Best of luck. 

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