RevolutionMX TTR-style 155z... The wait is over..

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Okay, i've had the bike for a couple of days now, and spoken to a few other owners, and have gone over the bike with a fine tooth comb to see any faults or issues... some have already been documented, others will come up over time.. so here is what i've found so far...

Fuel cap: Seems poor machining and quality control is the problem, same as the Ciniworx bikes... the cap doesnt fit the thread properly, and wont screw all the way down.. i simply swapped mine for a better one...

Fuel line: when assembling the bike, hook the fuel line up to the carby BEFORE you turn the fuel on... otherwise you end up with a shoe full of petrol like myself and hellrazor did.. ha ha ha!!!

Air-screw: the air screw appears to be turned all the way in, as delivered. i turned mine out 2.5 turns, perfect. :)

Rear Brake lever: mine was fouling a bolt head on the clutch cover, and was holding the back brake on... Simply bent the lever out a little, so that it clears the bolt when returning to normal position.

Rear shock protection: Needs a shock cover. Will make one out of inner tube for now, until i can source a proper one, just to keep mud and crap out of the shock and seals...

Jetting: so far, so good as delivered, with both the 155/160 and the 175 engines..

Throttle housing: had an issue with mine sticking, but this only appeared after a little while... didnt happen striaght up out of the box. Where the throttle tube joins the throttle wheel, the tolerances arent perfect, and there is a slight lip, that grinds into the bars, and after a little while makes the throttle stick... i simply pulled mine apart, ground down the lip nice and level with a dremel, and reassembled. hey presto, dead smooth throttle action, no more sticky throttle.

I'm riding the thing on wednesday on a variety of tracks, and will have pics and vids of the bike in action as soon as i can... plus the actual ride review.. hopefully that will answer a few more questions anyone has. :D

the more time i spend going over this bike, the more impressed i am at the actual build quality, and the value for money. Truly epic. :D

me and a mate got the bikes, ran 2 tanks of fuel through them and they ran fine. after running them in we opened up the throttle and they were running like ****. so i changed the main jet from 112 down to 105 and my mate went down to 102.5 and they are both running sweet!

also had all the other problems, easy fixes though.
 
me and a mate got the bikes, ran 2 tanks of fuel through them and they ran fine. after running them in we opened up the throttle and they were running like ****. so i changed the main jet from 112 down to 105 and my mate went down to 102.5 and they are both running sweet!

also had all the other problems, easy fixes though.

112?
you telling me thats what they come with standard?

friggin chinamen cant trust em to do anything, pretty sure they were told to go 98 or 100..

but also guys youll have to dial in the needle cause thts another thing the chinamen cant do
 
me and a mate got the bikes, ran 2 tanks of fuel through them and they ran fine. after running them in we opened up the throttle and they were running like ****. so i changed the main jet from 112 down to 105 and my mate went down to 102.5 and they are both running sweet!

also had all the other problems, easy fixes though.
yeah, had the same issues with mine. even with the 175, it's still jetted wayyyyy too far on the fat side...
its wednesday Thump!!! waiting :D
wednesday has been and gone, had issues with my carby and throttle, proper ride review coming on saturday.. wasnt actually able to ride the thing successfully....
oh and does anyone know what wieght the oil is in the forks?
Not yet, but i'm working on a solution to the stiff/harsh feel of the forks..
112?
you telling me thats what they come with standard?

friggin chinamen cant trust em to do anything, pretty sure they were told to go 98 or 100..

but also guys youll have to dial in the needle cause thts another thing the chinamen cant do

Sean, i noticed a few jetting issues with mine as well, with both engines...
pulled the carby apart, to find a K45 pilot, K44 needle (not JJH needle as specified) and a 112.5 main jet.
Perfect jetting for the 175 engine is K40 pilot, K44 needle on the second clip from the TOP, and K102 Main jet... air screw 2 turns out...
Russ is already onto the suppliers about the stock jetting...
 
lil bits and pieces...

Ok, i've spent a little more time with the bike, both engines, and even attempted to ride the thing... I suffered a few issues with the bike, specifically the throttle sticking... spent a lot of time chasing the cause of the problem, and have finally found the issue...

Carby/Throttle Sticking:
I had thought it was the quality of chrome facing on the slide, with a small imperfection maybe catching on the bore of the carby... it wasnt sticking with the engine turned off, only when it was running... and would stick at all different throttle settings.. sometimes just off idle, sometimes wide open... not ideal...
So i smoothed the slide with emery paper, no joy there, tried the throttle housing, throttle cable, leaner jetting, different float heights, all sorts of the usual tricks to sort it out... still no joy...
Then i noticed a slight kink where the cable enters the carb top... Those familiar with OKO's will notice that the 26mm fitted to the TTR155z doesnt have the curved carb cap... but a straight holder....
So i swapped the stock cap for one with a curved cable holder, hey presto, no more sticking throttle... anywhere...
For those with a TTR already, if you click this link OKO Australia - Flatslide Carburettors and scroll down, you can find a few different carb caps... the one you want is part # 3050... and sells for $35 from OKO Australia.. cheap permanent fix...
For those looking at a TTR, Russ has already contacted his suppliers for a solution, and will most definately be sorted with the next shipment of bikes...

Jetting:
Despite being very very specific in what jetting Russ wanted, he was supplied with jetting not really that close to what was ordered...
I opened my 26mm up to find a K#45 pilot jet, K44 needle and a K#112.5 main jet.. After testing a few different jetting combinations, i've found the best jetting for the 155z engine to be a K#40 pilot jet, Needle clip on the second groove from the TOP, and a K#102 main jet. This offered easy starting, great response off idle, strong seamless midrange and a very punchy top end. This jetting combination can be sorted with the spare jets offered with the bike in the spares kit. (Bloody good idea that Russ. Brava!!! )

Clutch "Slipping":
One other issue i noticed, that got progressively worse throughout my attempted "first ride" was that the clutch started slipping, until i was getting no drive whatsoever... so here's me thinking i have a brand new motor with a fried clutch... with less than an hour's running time...
Then i noticed the feel at the lever wasnt quite ''right''... a quick look at it revealed that the grub screw for adjusting reach and free play had rattled out a bit, and was constantly holding the clutch slightly engaged... Wound it back out, hey presto, perfect clutch again...
So for those with TTR's, adjust the little grub screw in the clutch perch until you have your desired freeplay and reach, then loctite the grub screw.... lest you end up with a "slipping" clutch like i did... ha ha ha!!!

Fork Action:
The action of the forks are quite harsh, and pretty stiff.. i'm working on a solution for this, so keep an eye on the thread... at this stage i'm thinking it's oil weight and height, i'll be trying a few different set-ups over the coming week, and will hopefully find a happy medium that will soften up the first part of the stroke, while still retaining bottoming resistance...
I'm thinking lighter weight oil, and lowering the height of it...
anyone beats me to it, post up the results in here asap. :D

Lots of Win:
On the plus side, i've fitted the OKO28mm from the Bling40, and this has transformed the 175 into a real fire breather up top.. the 26mm offered good punch down low, a strong mid range and top end, but didnt offer the usual sting up top that we've come to expect from the OKO flatties.. the 28mm most definately offered that.. just working on cleaning up the transition through the mid range, once i've found the perfect jetting combination, i'll post them up in here as well...

I cannot fault the action of the rear suspension... this thing hooks up brilliantly, and i was riding in wet sand... usually good for sapping power, especially with a small bike, running a small back tyre, and not a huge amount of power..
I thought the bike was perhaps a bit down on power, until a few guys watching commented on how well the bike was squatting under power, and kicking up a lot of debris behind me punching out of corners... So where i'm used to minis that dont hook up perfectly, so they ''feel'' powerful, due to the fact they're spraying gravel everywhere, the TTR hooks up and drives.. oddly enough, much like jap bikes with linkage rears... imagine that... ;) over rough ground, the rear tracks well, and is a stable little platform... only managed a couple of the smaller jumps (cheers rain, how does f*** off sound for next time????) and the rear handled them well without bottoming, and that was with the shock at the supplied factory setting of both compression, rebound, and preload settings, with a relatively quick old fat bloke weighing 88kg on board... so 95% of riders will love the action of the shock and linkage rear... :)
I've found both the 155 and 175 to be an absolute cinch to start, although the 175 sounds rattly, a common affliction with Z motors...
The clutch action is brilliant, and feeds the power on nicely, which was a bonus on a wet track with deep sand sections... combined with the linkage rear, it's easy to dial on huge amounts of throttle, and drive out of corners without spraying anyone within 20 feet of you with gravel.. :)

Given this is an entirely "new" model and bike, if the issues outlined above are the only ones to crop up, then i think Russ has done pretty bloody well... Small items such as the above were easily and cheaply fixed, and overall don't detract in the slightest, the great value of the bike, nor the quality... Keep in mind, this is the first batch, and the next lot can only be better again!!! :D
 
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good stuff thump...

the throttle sticking is pretty common in the oko range... i have a couple here that are real sticky.
tired all sorts of things like yourself and still had no joy, next to try is a heavier slide spring..

and like thump said there only minor problems, and i doubt everyone will experience the throttle problem..

as for the jetting, i cant believe those chinamen took strict instructions and threw them out the window..every single one of them as far as carby settings go...

thump and myself were asked what jets to run, i said 98/36 with a jjh needle for the 155z pretty sure thump said the same.
but lucky russ had a brain storm and included jets in the spares kit.

us round eyes lose again...:autogun::kev:
 
yeah i tried stretching the spring right out to try and get a bit more tension in it, but fortunately it's turned out to be the angled cable guide cap that is the solution. so far so good. :) The ones you have, are they straight cable caps, or the angled ones as well?
The 21mm oko i had, that had issues with the slide sticking, and that one also ran the straight cable guide... And the 26mm with the straight cable guide, is now causing sticky throttle issues on the bling40... hopefully the cable guide is the problem... and is now sorted.. :)
but yeah, bit dark at the chinamen for ''neglecting'' instructions with the jetting, and as you said, Russ's idea for the comprehensive jetting kit is a boon for owners, as the solution is already in the spares box. :D
 
yeah iv tried the 2 different tops, even lubed the hell out of them..

atm i have a 30mm fitted and when i change carbs i just change the carb and use the same throttle top and slide.. the problem is def in the carby.. strange tho cause it never used to stick or idle high, just happened to do it one day..
 
i'm working on it boys, things really arent going my way with the bike review lately... no good last wednesday, went out saturday to do some tuning and testing, and got absolutely pi$$ed on with rain... no pics or vid... as soon as i get a clear day, dry track, and a shooter, i'll get vid up asap. :)

PS: on a brighter note, the suspension on this thing is going to make it a great FMX bike... :D
also soaks up whoops like a fat kid soaks up donuts...
 
hey thump I'm liking the way you've torn this bike to bits and dished out the facts ;) lets potential buyers really know what they're getting...

I got one question, do the dnm forks have an air reservoir like the fastace? air valves in the bottom an all that? or are they more like GPX with straight forward oil in the dampeners? I guess you will find out when the time comes to change the oil... I have been against dnm forks from the beginning I just thing GPX style full adjustable zocchie copy's are easy as piss to work on... but for all I know the dnm are just as easy to fix.... after rebuilding a set of as-02's and the air valves leaking after so many rides I never wanna see a set of psi forks again lol

and have you checked the valve clearance in either engine yet? I don't think you have which is a real worry cuz lately I've found from lifan125 to lifan 140 to yx150 to yx160 (brand new) have had NO clearance at all.....

sucks about the jetting too, the chinamen are really taking the piss this time round, something SO simple that will make the bike run great out of the box and they couldn't even be bothered doing it, If I was russ I'd on the warpath finding out why they thought they'd get away with skipping such an important detail of the bike
 
You run your levers so far down?

Looks like it was run though, got any ride pics?
 
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