150cc T-rex Daytona motor - photos

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so the daytona strokers come with a shorter con rod. that would put more pressure on the side walls as the conrod angles would be greater. i went with the same length rod to eliminate this. but plug and play sounds nice.

let me know how the 160 compares to the 150 DOHC as i am about 2weeks away from getting this setup working as well. hopefully it murders everyone else and i loose my arms from acceleration.

is there any indication as to when the daytona strokers will be on the market hack?
 
HACKMUNCH said:
its been awhile, sorry. well our 4v dohc has been through it's paces.(running for 6months) just won a few races recently. no real major issues and maintance is down to the bare minimium (changing oil). we have not shimmed the valves since day 1 and the clearance is still in spec range. the engine has just recently been stroked to 160 (with daytona stroker crank). deck heigth is the exact same so it's just a plug and play gig. the engine has been started and heat cycled but not "real" ridden yet with the stroker. the dohc kits are on sale here in the US for like $1499 this month. IMO thats the way to go but we have another guy on the team that races the 167cc +r daytona and claims to be making the same power as the 150 dohc engine. time will tell. hope this helps
Click to expand...

That's good info, have you had any issues with the clutch basket rubbers?

If so how long are they lasting?
 
the rod ratio is not the greatest (like 1.55) but its not that bad. with a full skirted piston it should be fine. the daytona stroker cranks are selling now here in the US. firepower has them and so do these guys -> DAYTONA DUAL OVERHEAD CAM KIT when we switched to the 150 dohc, the origional clutch allready had about 5 hard months on it so once we put the dohc on we swapped out the stock plates for the kevlars that came with the dohc kit. the rubbers last about 2 months after that, then daytona sent us there newest upgraded clutch with different cush drive and since then we have had no isssues.
 
Some questions....

i have just pulled apart my engine to put the DOHC on. The problem is that it has a Hispeed 3mm offset pin in it designed for the Lifan engines. Now to put this in i have had to raise the height of the cylinder by 4mm or so. The reason for this is because any offset greater than 2mm needs to have the deck height looked at.

The cylinder was raised by 3mm but you can only add 2x cam chain links at a time, therefore I had to go with a 4mm height rise of the cylinder in total. So yes i am losing compression. The problem is that the cam chain tensioner is at its full extent, meaning the cam chain is close together at the bottom end (sorry hard to describe without pics).

So as a result, what is happening is the cam chain gets one loose side when under load and the other side becomes loose when decelerating. The result is the cam timing being retarded when accelerating and being advanced when decelerating. This causes poping when decelerating.
As you can make out i am losing power while accelerating and gaining Hp when decelerating because of this.

I have thought of options as to what to do next but the dilemma is the shorter con-rod and cylinder height of the daytona’s. Daytona’s run a 97mm rod compared to the Lifan’s 100mm. The only answer is to get the new Daytona 160cc stroker crank.

What length is the con-rod on these cranks?

Is it short to keep the piston height the same?

Or is it the same length and the piston travels 2mm higher into the head?
 
I spoke to BBR a while back about upgrade kits and they said the 160 crank and DOHC was just a plug and play gig. Their test riders said it was too violent in the dirt and went back to the 150 set up.
 
grnman said:
Some questions....

i have just pulled apart my engine to put the DOHC on. The problem is that it has a Hispeed 3mm offset pin in it designed for the Lifan engines. Now to put this in i have had to raise the height of the cylinder by 4mm or so. The reason for this is because any offset greater than 2mm needs to have the deck height looked at.

The cylinder was raised by 3mm but you can only add 2x cam chain links at a time, therefore I had to go with a 4mm height rise of the cylinder in total. So yes i am losing compression. The problem is that the cam chain tensioner is at its full extent, meaning the cam chain is close together at the bottom end (sorry hard to describe without pics).

So as a result, what is happening is the cam chain gets one loose side when under load and the other side becomes loose when decelerating. The result is the cam timing being retarded when accelerating and being advanced when decelerating. This causes poping when decelerating.
As you can make out i am losing power while accelerating and gaining Hp when decelerating because of this.

I have thought of options as to what to do next but the dilemma is the shorter con-rod and cylinder height of the daytona’s. Daytona’s run a 97mm rod compared to the Lifan’s 100mm. The only answer is to get the new Daytona 160cc stroker crank.

What length is the con-rod on these cranks?

Is it short to keep the piston height the same?

Or is it the same length and the piston travels 2mm higher into the head?
Click to expand...

this is the reason i say you need to change the conrod to a shorter one when using an offset pin.
too many problems to chase by lifting the barrel.. stud lengths, cam chain blah blah..
 
yes that is true but there is more angle on the conrod when its shorter and getting a shorter conrod than what is already in the daytona's is hard.

The daytona runs a 97mm conrod and the lifan engines a 100mm. do you have any suggestions of conrods that i can use that are between 96mm and 94mm that will take 22+wrhp? it still wont help my cam chain flop though i guess.
 
yes the new 160 cranks have a shorter rod. 96mm or a tad shorter i believe. becarefull with the cam chain tensioner mech on the daytona if you have the cam chain tight as hell the bottom roller wheel will eat its self up bad.
 
im going to start my new motor today and run it in at the track tonight if possible. ill give u updates in the coming weeks when i do some laps on the thing. heres a new pic of the motor all mounted up.

WarrnamboolTeams253.jpg
 
You headed to Sth Dandy? I might come for a look-see! I'm supposed to be training tonight but I pulled attachments in the back of my knee :(

Looks like the retaining clip on the front breather oil line needs to be moved into clamping position.

What's the go with drilling the "break hole" so far up the gear lever? I'd personally have it further down so that I might be left with a usable stub in the event of a crash ;)

PS, is that a 28mm or 30mm carb I see?

PPS, round slides are for wimps...

PPPS, you can hang sh!t on me once you flog me 'round a track :D
 
i didnt put the clip down just yet as i was in the process of installing everything and the braided line is getting shabby. (it petrol tank over-flow that one)

Break hole- i dont care where is snaps just as long as it snaps and doesnt bend the shaft. i bring a spare to the track everytime so there will alway be a usable lever.

its a 28mm Keikin that im probably going to sell as i have a new one.

mate round slides arent for wimps when you are running an engine like this. you are a wimp for riding a nearly stock 150. this will have twice the power as yours so i cant see any wimp factor in that.

im not going to wait until i beat you round the track to pay you out. ill start now. if i was only half to a full a second slower than you on the other bike i rode, your dead now. real tyres, real suspension real motor real brakes.......bye bye.

i dont have a trailer for tonight so ill see what happens with riding it.
 
Looking forward to the vid grnman.

Spoke to the guys in the US, they have had a few crank failures, so they're working on a new billet crank that will utilise the takegawa ignition cover, that has a bearing pressed into the cases.

Also heard that Daytona are making some heavy duty cases, but not sure if they are necessary or not..

Think these items are 1-2 months away, so l'll properly but my build on hold until they are available.
 
grnman said:
i didnt put the clip down just yet as i was in the process of installing everything and the braided line is getting shabby. (it petrol tank over-flow that one)

Break hole- i dont care where is snaps just as long as it snaps and doesnt bend the shaft. i bring a spare to the track everytime so there will alway be a usable lever.

its a 28mm Keikin that im probably going to sell as i have a new one.

mate round slides arent for wimps when you are running an engine like this. you are a wimp for riding a nearly stock 150. this will have twice the power as yours so i cant see any wimp factor in that.

im not going to wait until i beat you round the track to pay you out. ill start now. if i was only half to a full a second slower than you on the other bike i rode, your dead now. real tyres, real suspension real motor real brakes.......bye bye.

i dont have a trailer for tonight so ill see what happens with riding it.
Click to expand...

Hahaha, I want you to be faster than me (but not as fast as Barnes), if I'm chasing you down I'll get better quickly... Then I can try keeping up with Barnes ;)

The bet is still on; I need to pick up my corner speed and this will be the best way to do it (and suitably hilarious when I lose)!

Let me know when you're gonna run the beast in, I'm very interested to see it going. Hopefully you can hang onto it :p

The round slide will be better for running the bike in... What's the new carby, another Keihin?

I'm not a wimp, but my bike is :p
 
tried to run the bike at the track tonight but it was a no go. the jetting was waaaaay to lean and the header pipe glowed red hot after 1min of run time so i shut it off. with the genuine Keihin PE28 the biggest i had was 40 pilot and 132 main. this wasnt even close. ill have to order some jets and try again.
 
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