Malossi BBK for People 50 2T

[chaz35]

Good report!  I'm gun-shy of mine, you know blew up 2x's already, but I think can take some abuse.

Mine likes OEM pipe, my CVT staying in lower gear too long, needs tuning.  You probably just need lighter sliders/ rollers.  A few adjustments to CVT really changes where engine likes to run has been my experience.

Where are you getting your Dellorto parts?  I know about the 4T atomizer, maybe it's there because it works OK.  Malossi says was set-up for BBK engines, right?, and was working for you?  I read instructions for that carb and when mine comes in I will check if has the listed components.

I guess 19mm carb helps it get enough gas compared to OEM carb, plus I am running pod air filter, maybe getting more air?, so mine is running lean.  Be glad when I get mine sorted out a little better, thinking the larger slow jet may fix mine.  Mine seems to run cool WOT, but afraid to leave it there for long.

I understand you have oil pump connected, but cable removed, so must be adding oil to gas, how much oil you adding to gas?  Cheers

[paceneedsstides]

I'm adding 40/1 premix but pump is still adding idle speed amount of oil plus I think a bit more when at WOT due to more vacumn on pump. I have so far gotten all my Jets and atomizer and such at trealand.tv they have a specific area in parts section for Dellorto PHBG. running rich in idle didn't help mine I swiched back to original but am still owrking on getting main to not be rich at WOT

[paceneedsstides]

Just follow the red lol

[chaz35]

OK treatland for Dellorto parts, that's cool.

I think my carb is messed up, took out yesterday with 52 slow jet and ran better, but not right, high temp 400f.  I am pushing harder, only have less than 10 miles to complete 500 miles break-in.  Engine will not run steady, I think sign of lean condition.  Good thing I have CHT or probably sized engine by now.

I plan to take carb off and give a good cleaning, is if that helps.  My 2005 S9 had carb issues with slow jet and took several cleanings to finally get it clean, must be some really small passages in there.  Cheers

[paceneedsstides]

go with biggest main jet you got it shouldn't be at more than 375 or 280 at WOT but some run hotter puttering around when not at WOT.

[chaz35]

I cleaned carb, don't think that was the problem.

Then I worked on the needle, would be great to raise the needle a little.  The needle was bent a little, don't think that was the issue, but got it straight.  wordslinger has a good thread how he raised the needle for the OEM carb, so I tried doing it and was able to get 1 shim installed, like he did. 

I also thought about sanding the needle to make it thinner, but probably not a good idea, and decided would be better to try and raise the needle.  Also, thought about drilling out the needle jet to in effect make the needle setting richer.  I don't have a spare needle jet, so will put that off for awhile.

I already have largest main jet 108, and fairly large slow jet 52 installed.  I put it all back together and went for long ride.  Could tell raising the needle had some effect.  Still wants to run too hot, and still not holding revs steady, but a lot better, was actually fun to ride.  High temp was 380f, but was easy to keep around 350f, would really cool down fast, if got off the throttle.

I think this carb would be great, if had adjustable needle.  I looked and looked, but couldn't find any different size needles for this carb.  With pod airfilter, probably getting too much air for the jets/ needle to handle.  Probably would run OK with OEM airbox, I don't know.

Installing Tecnigas Next-R pipe next, then tuning CVT.  Max revs today was 9600, should turn more with pipe.  I am hoping carb goes better with Tecnigas pipe, we will see.  Cheers

[chaz35]

I was able to raise OEM carb needle 3 shims, made some difference, but still running hot, high temp was 388f, but ran a lot better.  Next on carb, I will try drilling out main jet.  I have a micro drill set and should be able to easily drill it out to the next larger size.  But 1st I will install Tecnigas pipe and see how it goes.  Actually, I was pretty frustrated with how it's running after messing with so much.

Extra shims on the carb needle was cool.  All you have to do is shave down the top of the needle to a smaller OD and it will fit up inside the plastic retainer.  Actually, appears was designed to allow for shims, but the top on the needle is too large OD.  With a little more work, could probably add 4 or 5 shims, but probably not necessary.

OK, got pipe installed and think this may be the solution.  Started raining, so haven't gone for ride yet, but was surprised how quite, probably less noise than OEM muffler, especially the carb.   The carb was really loud, but appears giant sucking sound has gone away.  I also looked up the exhaust port and could see the piston/ rings and cylinder were in really good shape.  If runs well with pipe I will be very pleased.  Cheers

[chaz35]

a few pics/ vid:

[paceneedsstides]

Nice let me know how you like that pipe bro I love mine only thing I might do is get the Tecnigas RSII chrome for it. That pipe alone being first thing I out on gave me my biggest performance increase of anything.

[chaz35]

Took for long ride with Tecnigas NextR pipe installed and was a lot better, but not there yet.  If I didn't already have S9 LC that runs like a champ, I would be very pleased with this BBK, but I am already spoiled and know it can run better.  Problems:  still running too hot, high temp >400f , and has too much HP/ torque for gearing.  With pipe, sounds better/ quieter, runs cooler, but power/ revs not significantly different, high revs approx 9600rpms.  Apparently, OEM exhaust was really good, but pipe better, worth the extra $'s.

So what to change?  could drill out main jet, drill out needle jet, raise needle some more, or install Malossi variator.  I installed the Malossi variator with included 9g rollers, and went for fairly long ride, and it made huge difference.  I think main benefit of Malossi variator is more top end, because the Malossi variator has larger variator OD.  It doesn't look like much, but makes difference.  The BBK has so much torque, don't really need the other benefit engine rev'ng a little more, but does have nice effect too.  All in all, I really like the Malossi variator and recommend it for 49cc and BBK set-ups.

Engine ran a little cooler, but still gets too hot cruising.  It's cool at idle, and WOT, but cruising with very little throttle, the temp really climbs, high temp >400f again.  I think slow jet OK, main jet OK, but needle is too large, doesn't let enough gas flow, so runs lean, from approx 1/4 to 3/4 throttle.  So, next adjustment is to raise the needle some more, I think I can add 2 more shims for a total of 5 (approx 1/10 inch or 2.5mm).  If that doesn't do it, then I will probably drill out the needle jet.

I do have the Malossi 19mm carb kit now and will eventually install it, but haven't given up on the OEM carb yet.  I originally wanted it to try on 49cc S9 LC engine, but now think may need higher powerband pipe to really benefit from it.  Maybe I will get Tecnigas Trek or Triops after I install the 19mm carb?

People 50 with BBK is starting to be really fun to ride.  It feels a lot faster at the red light drags than the S9 LC, and with the Malossi variator has similar top end.  When I get temp problem solved, will be my best/ fastest scooter.  Cheers

[paceneedsstides]

I would do that carb swap bro bigger carb is supposed to help keep BBK cooler. I am running rich cuz with almost your setup and the 19mm carb I can't get over 350 I think once with my daughter on it riding around and going uphills and everything I got up to 360 but, with just me I usually don't top 340 or 350 from idle-WOT. usually around 310 so I gotta tune mine lol but rather run cool than hot.

[chaz35]

pace, yes you are right, but will be big project for me, messing with throttle cable...

I looked at Tecnigas pipes, I don't think they sell RSII anymore, just saw Trek, and Triops.  I think Trek has higher powerband than NextR, the Triops higher still?  I did see scooterpartsco has Tecnigas RS for good price, maybe that's the one you are looking at?

Check-out this comparison chart:  http://www.pedparts.co.uk/c/asset/tecnigas/tecnigas-standard-50.png

Cheers

[chaz35]

Did one more mod on OEM carb, was able to raise needle approx 1/8", which is a lot, approx 6 shims total.  Weather raining next few days, will test next dry spell.  Figured out I don't have large enough micro drills to enlarge main jet, these 2T main jets are huge compared to 4T engine carbs I used the micro drills for.  Hoping needle adjustment will do it, if not will probably install 19mm carb next.

Compared 19mm to OEM carb, outside size not much difference, think I will really like it once installed.  Difference in barrels is huge.  Manual choke will be nice, but funny thing, OEM choke has been working perfect ever since I installed BBK.  My pod air filter fits the carb, nice surprise.  Needle has height adjustments, very good.

pace, have you adjusted needle height?

[paceneedsstides]

haven't adjusted needle height yet but is something I may do I have the 2T atomizer and 2T bushing that I may install again but when I tried it ran way to rich with even a 90 main in so I have to wait as don't have smaller jets. With the 4T internals I am running a 107 main pretty good. Do you have Pod filter on stock carb? that may be part but I doubt all the reason you're running hot. But I bet changing to bigger carb will help alleviate it some.

Also here is the link for the RS Chrome scooterpartsco has it for all us Kymco 2Ts
https://scooterpartsco.com/kymco-people-parts/kymco-people-50-2t/tecnigas-rs-racing-exhaust-for-kymco-50cc-2-stroke?zenid=dicph7rggo682i27orpdtv4o61

[chaz35]

Generally, needle controls 1/4 to 3/4 throttle.  Are you mainly riding WOT or less?  49cc engines I run WOT all the time, BBK doesn't need it, so needle is causing mine to run lean, I think.  Can't remember for sure, but think needle clip was on highest groove on my new 19mm Malossi carb, which would be leanest setting.  So, if yours came that way, it's already set to run lean, needle probably not causing yours to run rich.

Yes, I am running pod air filter on stock carb, and yes it's getting lots of airflow.  I just ordered set of welding tip cleaners to enlarge main jet, if I need to try that.  I thought I had micro drills to do that, but found out tonight mine are too small.

That pipe is sweet, I think makes more HP than NextR, but takes more revs to do it?  Cheers