z50 engine in motovert RX

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GROMMER

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Hi ...

My quest is to get a registerable, light, reliable, dirtbike that I can flat foot (28' inseam)

I am almost complete with my Honda grom with cbr300r engine and want a dirtbike with the above checklist.

Has anyone done a build like this? I know it would need engineers cert... but after doing the grom eng cert its pretty straight forward.

I am pretty sure the z50 engines are a straight swap into a thumpstar.

Would a kitaco 124se bore up kit be more reliable than a chinese engine?


any help/ experience / advice with this before an outlay $$$ would be much appreciated.
 
Yep z50/xr50/crf50 engine will bolt right in. If you get a motovert rx125 (rather than the rx50) i dont even think you would need an engineer as the new engine is the same capacity as the old one.
Now more importantly, we need pics of this 300cc grom!
 
kitaco 124se bore kit are awesome! Road few of them!
china motor fair few steps behind! kitaco motor
 
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as requested - the grom at near completion stage.

Thank you for your advice ..i have a mini boat also..

Im keen to get a dirtbike and i think a motovert RX will be my pick of choice i just want it to be reliable.. hence the honda z50 swap.. i have looked at all the normal bikes out there but they are either too heave or too tall ... and lowering something to have the same travel as an RX with all the extra weight and bigger engine seems a bit pointless.
 
That is insane! What a killer bike, an absolute masterpiece of engineering. Anyone would be proud to call it theirs, top effort
 
thanks guys should be up and running in around 4 weeks. I had to pay my CTP for it yesterday and went from 118$ for a 125 now to 290$ for a 300
Does anyone know anyone with a motovert RX? can they tell me about the reliability?
I rode a pit pro the other day but i think it had a DHZ engine in it and it was crazy! i loved it.. i am looking to get an RX so i can ride it legally and have some fun in the bush.. Grom will just be for onroad use.
 
wtf?
you stuck a cbr into a grom? and got it cert? (shame its not the mc22, cbr250rr with four pots...like a real CBR should have!)

whos ya engineer? how much he charge?

i gotta get my honda cub50 cert when i finally get it all together...

lifan 140, direct bolt in of course...tis why i kept this 50 frame.
front forks/disc brakes from R15.
EFI.
turbo.
bigger tank. (110 tank bolts straight on and is 5l rather than 3...)


all the above need certifying. about to go pay a visit to the local engineer (hornsby) and ask a few questions, such as can i get the mods only certified without having to complete everything, like lights, wiring, etc... as thats basic stuff. dont want to get it all done and then find out its rejected! i know he charges something like 180/hr consultation, or 600 odd for straight out check out/cert if allowed. five minute enquiries are free so far...

just finished my scavenge pump for the turbo oil, off to pirtek to see what they damage me for a couple of M8 banjo fittings. conveniently next door to the engineer...

yes, the turbo does boost... hit 8psi on one run so far. hoping that getting it down low, right next to the exhaust will help. more heat=better! hence the scavenge pump. plus i wanna get that extra hot oil through a cooler before dumping it back in the case...

dodgy video alert! this was the first incarnation to get it running.
[video=youtube;M5-vLxcdxQw]https://www.youtube.com/watch?v=M5-vLxcdxQw[/video]

i also got to put a bleeder valve onto that brass blocky thing between the pump, injector and regulator cus when it runs dry...its a prick to prime the pump again!

and make a new manifold/throttle body cus that ecotrons one is a POS...
 
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Lol cant help where this topic has gone

Engineer - Ian Davis - rod bods in Nabiac - and $990

There is 2 engineers in cardiff 1 put me on to Ian Davis.. he is a hot rod engineer.. but there is another guy in cardiff that does the z50 guys with takegawa engines in them..

Lol groms can only handle singles they are not wide enough to fit an mc22 into them haha..

Sounds like your build is pretty ambitious also ! how i did it is ai took pics and got the engineers ok for every part of the build before i did it.. some people make the mistake of doing the work then trying to con engineers for a cert...

i am thinking maybe even getting a non registerable thumpster now.. to just ride around for fun... can anyone give me info on if pit pro engines are better than lifan.. and are daytona anima 190 actually worth 2k?
 
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You had me at the labrador.. best dogs ever ! nice build !
 
hmmm...nabiac huh? just up around forster? hmmmms...
had a chat to the engineer (hard deciphering what he was saying...indian...must have changed owners since last time i went in a few years ago on some other project).

basically, i can get a cert with an engine of no more than 20% more power than the largest similar model (supercub 110, 8hp i believe) which basically limits me to a 125, NA... and yes, i can get the mods alone certified without finishing the whole damn thing. thats one good thing.

my attitude is as long as its done properly, it will pass... ive seen what some people do and its plain SCARY!

unfortunately, it will cost me something like 3000+ to use the 140 like i have, because it needs to get taken to eastern creek, so track hire, and test out the brakes(i think thats what he said?)...all in all, not what i want to hear! and obviously that hasnt been an issue with your build? (there is no way that that is less than a 20% increase in power!) so...i find a different, more bike friendly engineer!

like, seriously? cant you just take it down a quiet backstreet and do a brake test there? grrr... it had drums! its got a disc now! it does endos! it even whistles! (put a BOV on it after that video...)

all in pieces at the moment. banjo fittings are damn expensive so im going on the AN4 aero fittings track now... figuring out whats needed is another story altogether!



maybe i just get it registered and done then swap it over to the turbo 140 and risk it! heh heh heh. cover it up with duct tape so noone notices... that wont work. i want this FOR work! (courier...whats better than a postie but a souped up postie?)

ah well.


thanks. youve given me two leads to follow :)

as for the lifan... i have put both my 140's through hell without issues. even boosted, i havent got a sign of detonation. bit of clutch slip yes, but nothing else. of course, ill be buying a new one for road use...

friend had a yx150 in his pittie, it blew its crank bearings in less than a week... i had to tow him home with my best flanno shirt!

maybe i am biased, but i love my lifan 140's... even the 1p54 is pretty good, whereas certain other brands of engines have always had...problems. its why i have a shed full of them!
 
oh yeah, the new cam sprocket cover...

4 attempts! stuffed up three times on the first four holes!

last one went flawlessly...

20170731_223026.jpg20170731_223040.jpg
 
ok long update but its now got a z190 engine in it.. and am very impressed! it keeps up with a brand new commodore to about 90kph and have held out against a mazda 3 turbo to about 80kph.. the launch is incredible ! 26166106_10159765186615243_5065249768191875720_n.jpg 26112382_10159765186810243_8786312558067720443_n.jpg
 
very nice... and btw, i just came across a five speed box for a Z190 for...wait for it... just under 50 pounds. ooracing, in their sales section somewhere. may wanna snatch it up!+

https://www.ooracing.com/gearbox-kit-z190-5-speed.html (no VAT)

and, as for my project... blew the ECU due to a mistake on my earth rail...oops. just because theres continuity between the two blacks doesnt mean they are connected in a manner that will deal with current! fueled it up and pop. that was that. worked up until then. my guess is the extra current from having fuel pressure finally.

got new ECU. that just randomly failed after fifteen minutes or so. main processor decided to short its 5v and ground rails... sigh.

so, a PWK 26mm, and im away and laughing. still gotta tweak the tuning...both the carb and the pitot tube...


so much damn work...ruined by random component failure...


i have one chance, of managing to chop out the processor from the first ecu (would still connect to PC, hopefully still works) thats potted in epoxy, and graft it int the "new" ecu, that was potted in silicone and has had virtually all its components removed.

it just annoys me when i think how much better i could get this going with some ignition maps as well as fuel maps...
 

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