150cc T-rex Daytona motor - photos

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Alot of the vendors bash them because they cant sell them, daytona is strict who they sell to and you have to buy big quanities to even get them. Most guys in america that sell them drop ship them from the 2 importers that actually bring them in from daytona (hence the higher prices) vegas minimoto is proof that the daytona is for real, 5 out of the 6 podium spots in the 2 pro classes were running daytona engines. The other spot was filled by ryan beat on a klx 195+r engine. You get what you pay for period.
 
The mega cam looks like it has a bigger nose radius (more duration at full lift) than what others are selling ... They all claim to be Z-40's ... but at a much higher price ... and the lobes look different in every pic ... LOL ...

Classic Honda 50's Australia - DRP Super race camshaft Z40

Rovaza

Motovert - Australia number 1 brand of performance mini bikes

Z40 Cam kit - YX140 | PitPro Dirt Bikes Australia's Largest Online Pitbike Store

HIGH PERFORMANCE Z40 CAM KIT YX140 BOOST ENGINE 2HP - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 08-Feb-10 11:39:24 AEDST)

As for the Daytona's ... Nobody is doubting they're a great motor ... but it's things like THIS which put people off 'em ... WHY is the ignition system priced so high ? ... Pure gold used instead of copper ? ...

Motovert - Australia number 1 brand of performance mini bikes

Motovert - Australia number 1 brand of performance mini bikes
 
lol MOJO parts prices are extremely inflated.....
but yea the price is pretty high from legit sellers too
 
What most of the guys who blow the cranks or shatter the pistons in the Daytona 150's don't tell you is that they're using them for motard and more than likely holding sustained peak revs on long straights ...

Personally I think the guy who reckoned the motor blew within 4 hours from new isn't telling the true facts ... You can see by the gasket goo on the bottom of the cylinder that he's probably had it apart before ... Some people add heavier than stock Hi dome pistons without re-doing the balance factor ... then go racing the engine ...

Maybe the Daytona's are precision balanced to suit their intended usage or maybe they aren't ...

Some info on the importance of engine balancing ...

Crankshaft Balancing:Theory 101 Henson Racing Engines Oklahoma

Here's a PM thread on the Z155 vs Lifan 150 for street use ...

Firepower354 tends to go for the Lifan 150 ...

155z Vs. Lifan 150 - Planet Minis
 
has there been problems with lifan 150 motors tho?

I've never heard 1 complaint about a lifan 150.... maybe cuz there's not many out there compared to YX's I dunno but they seem to have a real good rep for reliability
 
I personally have a lifan 150 as do a few of my riding mates and we have never had any problems with them,infact i like them that much ill be looking for another shortly to go into my rx they are great motors and pretty reliable
 
Notice most of the Yank vendors always crap on about YX or Zongshen motors saying you can buy more bits and pieces for them ? ... That's because they WANT you to buy the engine you're going to end up having to spend the most money on ... so they can make a mint out of everyone ... LOL ...

Ask yourself WHY they can get parts for YX's and Zongshens ... but not Lifans ... Between DHZ , 4322g and several others ... They've got cranks , cases , trannies , piston and rings , heads , cams , ignitions , cylinders etc ...

If not for Firepower stating what he stated , they'd have spread it REAL thick about there being no mods for the Lifans ... You can buy Takegawa heads to suit BVH stud pattern Lifans , YX140 , Jialing GPX's etc as well ... plus every grind of Takegawa roller cam ...

Minimob Racing Takegawa Kitaco Mikuni Keihin

You can bore the YX150/160 and Z155's out a lot bigger ... but you can also put them out of balance easy too ... or have to run a short cut piston with a very short cut life span ...
 
Update on my 2 Daytona's 150e one I used for dirt one and the other on motard, neither have missed a beat.

My motard motor done easy 30hours and is going stronger then ever, it been ported, new cam, piston and carby and with the full race slick Vee rubbers tires its smokes the wheel up in 4th in a straight line.

My dirt motor in my LXR has done nearly 20hours, and has a new cam and carby. It hooks in the bush, other weekend went out riding with a mate on a 08 crf 250, crf 150 and a motovert 250 and never could touch it down low, yer they flogged me in the straight having more legs but off the line I left them for dead

One of my best mates got a LXR with the standed 160 and it cant get near the 150e, off the line it roost it and then wide open he maxed out in four going hard and im half throttle beside him

The 150e is a great motor and if you look after them with oil changers and a clean oiled air filter then last well over 30 hours with out needing rebuilds
 
Glad you guys like the daytona, we have been testing them for months too. We have one with about 25hrs of hard pro level mx riding on it and we have not broken or replaced 1 part. With a z40 cam and 2 added base gaskets(to give you valve clearance) the engine really hauls as$. We are now testing the upgraded daytona cam and hc piston combo, so far so good, revs like a 2 stroke with the upgraded cam/piston. We are also currently working on a 170 cc kit (actually 168cc) it will be available for the dohc 4 valve head and 1 for the 2v daytona head. If all works well we will be running a 170 dohc 4 valve at vegas this year.
 
HACKMUNCH: would this bbk for the daytona fit a lifan 150 also?
also... is it a full skirted piston?
 
I am not sure about the lifan 150 as the 170 (167cc actually) kit for the daytona is a scut set up. I am not sure how far the rod drops into the case on a lifan 150. The 170cc kit is 59 stroke x 60mm bore, we will be putting it to the test next week and will have a 170cc 4v dohc option also. Things are looking up with the daytona 150, gonna be alot of options here shortly.
 
ouch, 60mm bore doesnt leave much headgasket sealing area...
lifan 150 has same stroke but it depends if the bore height is the same too...

exquisit... give akunar an email.. he does 60mm kits for yx140's so i cant see why he wouldnt do one for a lifan 150... but to play it safe drop the bore size down to 59 or even 58mm.. 60mm only leaves 1mm wide on part of the head gasket.. 58mm will leave 2mm
 
well tony and spent some time last night mocking up a 60mm/167cc kit. so it's allmost a perfect square engine 59 stroke x 60mm bore. yes this is a TB jialing 60mm scut kit that can be purchased though any TB dealer like WHOLESALE CYCLE, FIREPOWER, JOHN ADAMS and so on. my one concern when we were talking about trying this a month or so ago was how well the cylinder would match the cases since the TB cylinder is 60mm and the daytona case are bored at 61mm (i knew the piston would drop into the cases), i was not sure how off center the bore was on the tb compared to the daytona cases. well they match up perfect, the daytona case are .5mm bigger all the way around so piston clearance would not be an issue. here is a look down the cylinder to see the cases matching well
scut.jpg




next was to figuire out how far the piston would drop into the cases to make sure it would be able to work. well the piston only drops into the daytona cases 1mm so it should be ok considering the klx 195 drops into the cases 3.5mm and i personal have seen those engines run for awhile and never saw one fail becasue of that reason. here is a look at the piston at bdc to see how much it drops in the cases
scut2.jpg




ok next was to make sure the piston to cylinder deck height was gonna be ok, considering the tb cylinder was a tad taller and the piston to deck heigth was different than the daytona piston. everything worked out well the piston is about .75mm in the hole but after we cc'd the daytona head and figuired out the math the 167cc kit comes out to a stout 12:1 compression ratio and has a ton of valve to piston clearance so running any type of cam will not be an issue. for reference the daytona head cc'd at 12.5cc, we will be working on a 60mm 4 valve piston to run a 167cc 4v dohc monster! here is a look at the piston at tdc. I JUST COPIED AND PASTED THIS FROM OUR FORUM MINIMOTOUNIVERSE.COM HERE IN THE US


scut3.jpg
 
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arnt the tb 60mm bbk's a skirtless design?

you say the piston only drops into the case about 1mm... looking at the pics mate theres alot more than 1mm in there..
 
yer alot more then 1mm in the case, why you using that piston to? is there not enuf clearance for a high top?

so all you done is got the jailing bbk?

ahha time to get another costume piston made, if that running 12to1 with they daytona cam and the hit to piston that be back to about 14.5

can you get more fotos plz im keen to build 2 for the dirt series this year
 

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