PW65 Malossi with WWB ceramic bearings

mat hormell /

Figured it was time to start a build thread on my 5 year olds PW50. Its currently a ported/ modified yt60 cylinder and 19mm mikuni carb and makes 4.5HP to the rear wheel. So we are looking to get him out of the dirt and into road racing and JR drag bike racing. I drag race with PMRA and he has been begging for street tires so... here we are...

What's planned:

Malossi 65cc kit ported /case matched and raised 0.080/ decked 0.080

High compression head with reworked chamber.

Modified cases

Stuffy built crank

Piston is being sent to Line to line coating to have thermal barrier and adbradable skirt coating applied.

Custom manifold and 19mm mikuni.

Modified 22mm header welded to FMF expansion chamber.

And last but definently not least

The whole motor and chassis will run on the baddest bearings on the planet! World wide hybrid ceramic bearings!

Chassis is being changed a lot as well. Will be going mono shock and running QT50 front and rear hubs laced into crf50 wheels. Will be ditching the pw body and modifying a pocket rocker body kit to fit the pw chassis. It will be a long drawn out project, that I will update thread on as progression is made. Motor work starts now!

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Re: PW65 Malossi with WWB ceramic bearings

Hopefully the updates come a bit sooner than every 5 years . ;)

Are you planning ceramic bearings for the wheels too ?

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Haha ya the bike will come together quickly, it suppose to be pure winter project, but I am like a kid when it comes to this shit haha. I can't wait lol!

Yes ceramic going in front hub, and every bearing in engine cases and final drive will be ceramics.

Re: PW65 Malossi with WWB ceramic bearings

Ana L. of the Aurora Roras /

Cool sounds like u could take it for a rip around too.

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

I'm also talking with to my engine coaters at Line 2 line about coating the final drive gears so I can run them dry, or with very little lube. Looking to cut as much friction and parasitic losses as possible put of this engine. So much power is absorbed in the final drive(edited)

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Oh yes a for sure, his current build runs 31 mph with me on it with the 60cc kit and qt50 rear gears and primary gear

Re: PW65 Malossi with WWB ceramic bearings

Jack Rutherford /

Is acceleration or top speed your biggest concern in these drag races?

Re: PW65 Malossi with WWB ceramic bearings

fuuuuuuck yeah, this is awesome. I've heard the Texas minigp series has a bunch of pw50 motards in the kids' class, but I never see them here and I've always wondered why.

Re: PW65 Malossi with WWB ceramic bearings

Yeah......local dude who is a stella builder experimented with ceramics.

I would not do it. Yes, motos use them. But those engines are built within a very tight tolerance spec. Its not for benchtop builds unless you like asplodin

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Will be acceleration and top speed around 40-45 would be ideal for now. They race 1/8 and shorter 480ft I think it is

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Unfortunately they don't start racing until 8 years old in the mini gp, but we have a perfect spot for a training course for me to teach him on until then

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

There are alot of Shit ceramics bearings, but WWB world wide bearing is the best in the world, used in every high performance racing engine professionally across the board and nothing new to 2stroke racing engine or high tolerance motors. This bearing kit is $500 for the motor, final drive and front wheel and Dave stands behind product 100%

> alex . Wrote:

> -------------------------------------------------------

> Yeah......local dude who is a stella builder experimented with ceramics.

>

> I would not do it. Yes, motos use them. But those engines are built

> within a very tight tolerance spec. Its not for benchtop builds unless

> you like asplodin(edited)

Re: PW65 Malossi with WWB ceramic bearings

Interesting, I don't know much about the ceramic bearing stuff, most research I've seen puts all engine friction around 5-10% of total losses in an engine, that's for a four stroke. Most of the friction in a 2t is from the rings, and those numbers would change because a 2t is less heat efficient. So rough numbers maybe .01% increase in engine output from swapping to ceramic bearings? Either way it looks like this will be a very high standard build, excited to see the progress, not really a Moped but you're pretty in a good place to get some info about TUNING single speed 2t, not a lot of folks PUSHING that envelope and it presents some interesting challenges for sure

- EDITED FOR BAD MIDNIGHT AUTOCORRECT POSTING(edited)

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Its about 50% friction cut vs a standard greased ball bearings and like 60% rotational mass. I've ran them for years in my race bikes, in math you dont see the adnmvantge to them, but when you move to equal bike one with ceramics and one without, it is incredibly noticable

I'll post before abs after of the friction cut in the final drive before I swap them out for comparisons. My drag bike wheels will free spin for 5 minutes straight with these bearings. It should be a large increase in power from just the final drive bearings, no just resistance in this motors final drive

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Just for the record, so there is no confusion, I'm no amateur engine builder, been building 2 stroke flat track engines since I was a teen ager, been a motorcycle mechanic as profession for 12 years, built my drag bike from the ground up in my backyard shop, ai have plenty of expiernece in this field. This is such a simple motor, already tripled the factory horsepower with minor tweaks and adjustments, looking forward to building it to be the best it can be. For the ring friction, I do have a solution for. Once the thermal barriers and skirt coatings are applied to the piston, I will send it it Micro blue racing to have the cylinder walls rings, piston ring lands, pin and bearing all micro blue coating. It's a friction reducing coating, tungsten disulfide that is applied to walls and metal to metal surfaces, retain oils and has a fraction coefficient of. 001%. This helps with keep everything oiled and prevents seizing while reducing friction. All these things I am doing have been treated vigorously with my racing bikes, should be a super fun project and I'll get to teach my little man so much through the process.

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

End goal is to look something like my race bike styling as an end product.

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Re: PW65 Malossi with WWB ceramic bearings

yeah thats pretty cool stuff. i've worked with TiN and DLC coatings at work on a few engine components where it gets used something like 'super duper case hardening' just giving the components a little more case hardness and in the case of the wrist pins slightly better performance in mixed-mode friction.

There is a lot of stuff on the market that gets sold with some pretty spectacular claims, when i've worked with it in the past its been in a specific application where it was more cost effective than a redesign or not possible to use conventional stuff... but that was OEM production so super cost sensitive.

i guess its probably a good option to use some coating on the cast iron, but most moped folks go to a nikasil kit for high performance stuff, along with a 1.5mm single ring instead of the double heavy cast iron rings in the malossi. Also the single ring weighs less and seals up better at high rpm so you got that going for you.

what is the class you guys are running? how far is the distance? i didn't even realize there was such a thing as junior motorcycle drag racing, probably a lot of moped tech that could apply. they sprint race these things in europe, guys like OVC and PSR have youtube vids of some scary fast straight line mopeds.

Re: PW65 Malossi with WWB ceramic bearings

ope, my bad, 480 feet, thats rad. My tomos sprinter was hitting 60's in a couple blocks tach'd out on a 45mm/ 68cc kit so hurtling a kid into the 60's on a PW50 in 480 feet should be pretty easy.

getting his mom to go along with it on the other hand...

yeah post up the specs for the race class, there are lots more better options for scooter cylinders and stuff that you can definitely find something that will blow anything out of the water, these scooter kits are pushing 20 hp on 50 cc's. I haven't built that malossi kit but i think its pretty close to the hobbit one which is a turd.

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

I think the malossi will serve as a good power increase for him while he is small enough for the pw. If he gets real serious about it, we will probably buy a cobra dirtbike and convert it to a supermoto.

I have looking into changing rods to get the 12mm pin, then absolutely options open up so much! I think 20hp on a pw would be way to much lol

> Graham Motzing Wrote:

> -------------------------------------------------------

> ope, my bad, 480 feet, thats rad. My tomos sprinter was hitting 60's in

> a couple blocks tach'd out on a 45mm/ 68cc kit so hurtling a kid into

> the 60's on a PW50 in 480 feet should be pretty easy.

>

> getting his mom to go along with it on the other hand...

>

> yeah post up the specs for the race class, there are lots more better

> options for scooter cylinders and stuff that you can definitely find

> something that will blow anything out of the water, these scooter kits

> are pushing 20 hp on 50 cc's. I haven't built that malossi kit but i

> think its pretty close to the hobbit one which is a turd.

Re: PW65 Malossi with WWB ceramic bearings

Ana L. of the Aurora Roras /

DaMn!!

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

> getting his mom to go along with it on the other

Lol! Yea she knew what she signed up for when she married me, I was surprised how well she took to him picking up riding so young, but she's let us boys have our fun haha

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

What I found with Micro Blue that made me a true believer was my CCP before and after having the coating was done to my pistons in the Race bike. I was at 220 CCP cold before and 245 CCP after, No other changes. Better ring seal due to better oil retention and keeping the piston true to its bore " line to line". As well and the skirt coating also helps promote better ring seal, which is where the Adbradable skirt coating comes in and is so bad ass, especially when using a billet aluminum piston in a cast iron cylinder, the expansion rates are so vastly different, you typically have to run huge piston to cylinder wall clearance, but with this skirt coating, I ahve them build it up to be over tight and then hone the coating down to be a perfect fit, it then breaking in under operation to be 1 consistent clearance across the whole skirt. This is not like your typical skirt coating you would find on such like wiseco from manufacture, entirely different, pretty amazing stuff. I had 2 season on my race bike pistons and the skirt coating still looked brand new. makes a huge difference when you dont get piston rock and TDC and BDC.

Also something cool, you can use the coating to cover up scuffed skirts and resure hard to find pistons as long and the lands are in good shape, L2L can build back up your skirts to be better than new.

> Graham Motzing Wrote:

> -------------------------------------------------------

> yeah thats pretty cool stuff. i've worked with TiN and DLC coatings at

> work on a few engine components where it gets used something like 'super

> duper case hardening' just giving the components a little more case

> hardness and in the case of the wrist pins slightly better performance

> in mixed-mode friction.

>

> There is a lot of stuff on the market that gets sold with some pretty

> ty spectacular claims, when i've worked with it in the past its been in

> a specific application where it was more cost effective than a redesign

> or not possible to use conventional stuff... but that was OEM production

> so super cost sensitive.

>

> i guess its probably a good option to use some coating on the cast iron,

> but most moped folks go to a nikasil kit for high performance stuff,

> along with a 1.5mm single ring instead of the double heavy cast iron

> rings in the malossi. Also the single ring weighs less and seals up

> better at high rpm so you got that going for you.

>

> what is the class you guys are running? how far is the distance? i

> didn't even realize there was such a thing as junior motorcycle drag

> racing, probably a lot of moped tech that could apply. they sprint race

> these things in europe, guys like OVC and PSR have youtube vids of some

> scary fast straight line mopeds.

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

> Graham Motzing Wrote:

> -------------------------------------------------------

> yeah post up the specs for the race class

I'll get the information about the local class, so here is the deal with jr drag racing. The NHRA use to allow it and it was part of their sanctioned events. About 12-15 years ago, NHRA determined it was "unsafe" to race in the most safe environment possible in motorcycle racing, and banned it from all NHRA sanctioned tracks. Total BS, and many of us parents have been fighting it. Some for many years. So what we are stuck with now is local non sanctioned tracks that will allow it with a signed waiver. Its bracket racing, so really doesn't matter how fast it is, more that its consistent, but we both want it fast lol. Ivw been working on building a local league and been talking with the local tracks as I attend them and most wre totally for it, just tskea getting a group of parents together, finding a track and starting something up. Most tracks already host JR drag car racing so it can easily be piggy backed with their events. Here some pics of jr bikes from the NHRA days

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Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

Anyways, as for an update to the build progression, I stripped the case halves and dropped them with my powder coater. I am having the cases and the cylinder head Cerakoted dark gunmetalish silver color. Will probably pick up the wheels next week and get them laced up and trued. Once I get the cases back, I will begin port matching the cylinder/cases and begin the port clean up on the malossi cylinder.

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

> Dave & Bummerzz Wrote:

> -------------------------------------------------------

> fuuuuuuck yeah, this is awesome. I've heard the Texas minigp series has

> a bunch of pw50 motards in the kids' class, but I never see them here

> and I've always wondered why.

Yea man it's the Texas Minigp, they race about 45 minutes from where I live, I cant wait until hea old enough to join, starts at 8 years old. It's like a riding school for kids + racing

Re: PW65 Malossi with WWB ceramic bearings

> mat hormell Wrote:

> -------------------------------------------------------

> > Dave & Bummerzz Wrote:

>

> > -------------------------------------------------------

>

> > fuuuuuuck yeah, this is awesome. I've heard the Texas minigp series

> has

>

> > a bunch of pw50 motards in the kids' class, but I never see them here

>

> > and I've always wondered why.

>

> Yea man it's the Texas Minigp, they race about 45 minutes from where I

> live, I cant wait until hea old enough to join, starts at 8 years old.

> It's like a riding school for kids + racing

That's cool, the lil ones here start on crf50s and move up to 100s and 2t 65s.

Sucks to be 30 getting passed on the outside by a 10 year old on a KTM 65

Re: PW65 Malossi with WWB ceramic bearings

Mikey Antonakakis /

Cool stuff! A couple thoughts, if you want 'em - depending on exactly how you want the engine to make power, a stuffed case may not be needed, and may be detrimental for power band (I think the guys that developed the Aprilia RSA125 ended up running pretty large crankcase volume because it made wider power?). And compression ratio/compression readings don't matter a ton when you're going for top power, because the pipe can stuff plenty of air in for it not to matter a ton.

My 50cc Peugeot has a pretty low compression ratio and large crankcase volume, and makes zero power below 8000rpm, but it makes a ton of power from 9k to 13k (13hp or so if I had to guess? Does over 65mph and accelerates quite well, pulls 5% grades at over 50mph. Gotta get it on a Dyno someday). I have the luxury of a well-tuned clutch and variator, so I can get away with a narrow powerband with low compression and hard-hitting pipe. That low compression is a bit easier on the motor too, I run very very low head temps even when ripping at top speed and climbing long hills. I almost don't trust my gauge because even after climbing up a 500' hill at 10% grade doing 30+mph, it says I usually hit about 140F. But I can easily keep my hand on the radiator, so who knows?

Things obviously change for single-speed applications, but you need tons of power for drag racing regardless, and with a centrifugal clutch, your launch phase (while clutch is slipping) is determined by the torque you make at the clutch slip speed. F=m*a, P=F*v, so at any particular speed, more power (to the wheel) gives more acceleration - which sounds obvious, but it means if you can downgear to let the engine rev higher and get into the powerband (especially after the clutch slip phase), you will often have more power available to you (even if there's less torque!). For instance, if you shift the powerband up a good amount to make more power, and sacrifice some torque to do so (let's say 10% less torque, but 20% more power), you can change the gearing by maybe 20% as a result. So the net impact is better performance all around, even when the clutch is slipping (roughly 10% better acceleration even with less torque).

My real 2 cents, it you're taking this much time and effort with this, it would be well worth it to get some good simulation software like EngMod2T. Costs less than your bearings, and has the chance to make a much bigger impact! 50% improvement on 99% efficient bearings only gets you to 99.5% efficiency, so a 0.5% overall improvement (even if you have a noticeable improvement in revvability). You can easily find several percent with better porting and pipe than what you get off the shelf.

Anyway, I'm looking forward to seeing more of this project! Good luck!

Re: PW65 Malossi with WWB ceramic bearings

mat hormell /

I appreciate the info and the interest! I dkt expect a major gain in power from the bearings being in the motor. The major increase in power comes from the final drive and the wheels. That's where they really shine. I plan to play with different exhaust configurations and what not but that will all be later once ita all together and being tested. I have a dyno so I can make minor changes to the pipe and see what it's doing to the power band. Here is the dyno run from his current yt60 kit, made about 4.25 hp on pump gas. I have it set up right now where it comes on the pipe as soon as it engages and run out around 8000 rpms

The springs dont engage the clutch til about 3500- 4k. It's like a rocket off the line with him on it already lol.

> Mikey Antonakakis Wrote:

> -------------------------------------------------------

> Cool stuff! A couple thoughts, if you want 'em - depending on exactly

> how you want the engine to make power, a stuffed case may not be needed,

> and may be detrimental for power band (I think the guys that developed

> the Aprilia RSA125 ended up running pretty large crankcase volume

> because it made wider power?). And compression ratio/compression

> readings don't matter a ton when you're going for top power, because the

> pipe can stuff plenty of air in for it not to matter a ton.

>

> My 50cc Peugeot has a pretty low compression ratio and large crankcase

> volume, and makes zero power below 8000rpm, but it makes a ton of power

> from 9k to 13k (13hp or so if I had to guess? Does over 65mph and

> accelerates quite well, pulls 5% grades at over 50mph. Gotta get it on a

> Dyno someday). I have the luxury of a well-tuned clutch and variator, so

> I can get away with a narrow powerband with low compression and

> hard-hitting pipe. That low compression is a bit easier on the motor

> too, I run very very low head temps even when ripping at top speed and

> climbing long hills. I almost don't trust my gauge because even after

> climbing up a 500' hill at 10% grade doing 30+mph, it says I usually hit

> about 140F. But I can easily keep my hand on the radiator, so who knows?

>

> Things obviously change for single-speed applications, but you need tons

> of power for drag racing regardless, and with a centrifugal clutch, your

> launch phase (while clutch is slipping) is determined by the torque you

> make at the clutch slip speed. F=m*a, P=F*v, so at any particular speed,

> more power (to the wheel) gives more acceleration - which sounds

> obvious, but it means if you can downgear to let the engine rev higher

> and get into the powerband (especially after the clutch slip phase), you

> will often have more power available to you (even if there's less

> torque!). For instance, if you shift the powerband up a good amount to

> make more power, and sacrifice some torque to do so (let's say 10% less

> torque, but 20% more power), you can change the gearing by maybe 20% as

> a result. So the net impact is better performance all around, even when

> the clutch is slipping (roughly 10% better acceleration even with less

> torque).

>

> My real 2 cents, it you're taking this much time and effort with this,

> it would be well worth it to get some good simulation software like

> EngMod2T. Costs less than your bearings, and has the chance to make a

> much bigger impact! 50% improvement on 99% efficient bearings only gets

> you to 99.5% efficiency, so a 0.5% overall improvement (even if you have

> a noticeable improvement in revvability). You can easily find several

> percent with better porting and pipe than what you get off the shelf.

>

> Anyway, I'm looking forward to seeing more of this project! Good luck!

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Re: PW65 Malossi with WWB ceramic bearings

Mikey Antonakakis /

Sweet!!

Re: PW65 Malossi with WWB ceramic bearings

♣Slew Foot♣ /

Yeah I talked at length to the bearing guys they swear if I put those in my moped I could just weld the case if I could only get needle bearings that were made out of ceramic to I would do it how they should be making ceramic Pistons by now with shuttle tile cylinders

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