KTM 65 SMR

[ringo]

Haven't done much except ride the 65 lately, here's a clip put together after round 3 of the championships, I make a couple of appearances including a stack (3:33)!!! Still finished third in that race

[video=youtube;JJi0dz7X15E]http://www.youtube.com/watch?v=JJi0dz7X15E[/video]

 

[Chops]

Fair few stacks there, most look not too bad except for that poor bugger at 2:06:11doh:

 

[xLOCOx]

thats MAAAAADD!!!

 

[ringo]

It was an awesome day Chops, the practice and qualifying was wet, race 1 was wet, race 2 was half dry, race 3 was completely dry and every race after that dry. It was race 2 that caught me out, I splashed through some standing water, rounded the hairpin and the track was fully dry so I fisted it! Unfortunately there was enough residual water left on the rear tyre to unhook it, bring it around and low side me off on the first lap!!! Still picked it up and finished 3rd after restarting stone motherless last!!

 

[motorman]

What a wicked clip.

WA definitely leading the way in mini supermoto.

Wish there was more in VIC. Looks like great fun.

 

[zwebx]

What a wicked clip.

WA definitely leading the way in mini supermoto.

Wish there was more in VIC. Looks like great fun.

+1 Stoney creek and broadford on selected days (stoney creeks pretty open) I would like a more local one if i could get a participating group to go

 

[ringo]

More riding, in Geraldton this time!!! Awesome little bike, but with two of the other riders clearly outpacing me and finishing third it's time for the 80cc kit I think!!! :grinning-smiley-003

The night sky, fire and beers were absolutely awesome!!!

 

[ringo]

Anyone who's in Perth will know what the weather was like yesterday, not conducive to staying upright to say the least!!!

Fortunately, I got all my crashing out of the way in Practice and Qualifying, staying upright in the races. Got 2nd for the day, two stroke power delivery is tricky as in the wet!!!!

 

[SwapperMX]

Great pic, this is damn cool !!

 

[ringo]

Hey guy's, time for an update!

The Athena 80cc kit has gone in as an interim measure because I felt the engine was due a rebuild and it would've been a waste of money buying a 65cc piston and rings when the the whole lot was coming out over xmas.

So, I've fitted the kit with stock carby (some jetting) and stock pipe to see how it goes!!! It goes mint!!! It's got alot more bottom end and even a tad more up top, I'd say due to the athena kit's porting!!

The plan now is to pull the engine out over xmas for a full set of transmission bearings and a new stroker crank to bring it up to the full 85cc that the class allows!! My machinist already has a hotrods crank and has started moving the bigend pin.

 

[ringo]

I'm also researching whether to modify an 85 pipe to fit or just get the biggest 65 pipe I can find, the other thing I'm looking into is replacing the stock 24mm carb with a 28mm that every 85cc mx bike runs!!! I'll be looking to pick up a kx85 or yz85 carb second hand once the full 85cc have been reached!!!!

 

[gottagetacheaperhobby]

Wow is that orange terror gonna scream when your done, the big 4 strokes wont have a chance!!

 

[63eh]

ringo how would you compare the size of your previous dhz to the ktm 65? is the ktm smaller?

 

[motorman]

Nice mate. Thing is going to be a weapon when finished.

 

[ringo]

ringo how would you compare the size of your previous dhz to the ktm 65? is the ktm smaller?

ktm 65 is crf50 china size
Ktm 85 is dhz/crf70 size

 

[ringo]

Wow, I haven't updated this since last year, how lazy of me!!!

Probably because the bike has been hard work at the moment, so here I go!!

Pulled the engine out over Christmas and had the crankcases relieved (channeled) so the extra stroke could be accommodated i.e. conrod didn't touch the crankcase on its way passed bottom dead centre. I cleaned up the path through the reed area and opened up all the transfer ports to look more like an 85sx. Had an 85sx base gasket, so used it as a guide and opened it all up somewhere in between 65sx and 85sx. Fitted the 80cc top end kit back on to the +5cc bottom end for a full 85cc!!

Went very hard, bigger change from this than just plonking on the 80cc top end on. Went really good until it overheated and seized, on further inspection I had not engaged the water pump shaft correctly when I installed the clutch cover!! Rookie error and major derp moment!! Piston wash looks good though, a little rich.

So went about rebuilding it, the machinist I've been using gave the hone a go in the barrel and sold me another piston, I gave the water pump a complete rebuild kit while I was at it and painted the clutch and stator covers black with some trick orange anodised cover bolts!!

So loaded up and took it to a Thursday night practice to prepare for raceday the Sunday after, 5 laps in and it flicked a piece of Nikasil and locked and spat me off again!!! Went home Friday night after work to assess the situation, pulled it down to find the damage and was left wondering how I was even going to race Sunday. Sipping on a beer, contemplating life I found a solution. Saturday morning straight down to SupaCheap Auto for some gasket paper to prop the 65sx standard bore up high enough to clear the extra stroke!! Cut out a couple of extra base gaskets and and threw the stock topend back on, calculations are about 69cc!! This should get me through the weekend!!!!

Rolled up raceday and it ran like crap, started throwing jets at it to cure the problem, starting to really dislike Mikuni Carbs!! Anyway, managed to pull off a 4th and two 2nds with a bike that kept bogging every time I executed a bansai move on someone. If I rode it really smooth it was fine, weird?? Anyway walked away with a nice little pocket full of points for the championship and 2nd on the day, great recovery considering where my mind was at the Friday night beforehand.

After pulling the bike apart it turns out the fuel overflow hose off the filler cap was squished under the tank mount...... Rookie error number2!! I was causing a vaccuum in the tank everytime I got rough with it and the fuel sloshed around.

So, ordered another Athena kit (this is starting to get expensive) and rebuilt it again, back to 85cc!!! This time I put the YZ85 carb, a Keihin 28mm, I had bought second hand out of the US on with a trick orange hose kit:

Chucked some new number boards on as well:

Went to Thursday night practice before round 3 of the champs to test, it ran mint all night, in fact the 28mm carb made a massive difference, it was short geared everywhere, so I pulled the 14t front sprocket off and put the 15t on. I was pulling the same gear, same corner harder than before, very impressed!!!!! Carrying longer gearing means the corner speed must've been higher too!!

I'm hoping this is the end of it!!

Plug looked way rich/safe so the Friday some orange mesh I had ordered turned up and I though what the heck do what you were going to do and cut open the airbox!!!

Looking schmick and ready to race!

 

[my67xr]

Far out that bike is so modded !
So you'll need to jet it richer for the next meet then, with the airbox no longer being a restriction ?

 

[ringo]

So Sunday comes around and everything is going well, the bike is hammering and I'm constantly running times within tenths of the quickest time. Completed two practice sessions and went out for first qualifying and the damn thing soft seizes again!!!!!! AAAGh!!!!

Couple of pics before it popped.

Popped the exhaust off in the pits to confirm my suspicions and looked up the exhaust port to see the scoring, it's overheated again!!

Damage to this piston is nowhere near as bad as the first time, but it's still overheating and it didn't as a 69cc the whole race round before???

So up to where I'm at now, ordered an 85sx rhs radiator from the US and an 85sx hose kit, orange of course:

Now the top hose is running right through where the coil used to live and the bottom hose doesn't line up with the rh radiator at all, I've now ordered an orange hose kit for a 65sx as well and will be looking at some T and Y pieces to make it all work, as well as relocating the coil who knows where!!!

Although there is no signs of detonation on the piston I'm starting to think that I should run the stock Athena head not the one I had machined out to run the bore lower. The port timing is great so I'm reluctant to move the barrel skywards but if this is a possible cause of the excessive heat then maybe it's my only option should the second radiator not be enough? 65sx's run a measly 550ml of coolant and the 85sx run 1000ml, plus the extra heat sink hanging off the front, I'm hoping this is the cure. I've also bought a trailtech tto temp gauge so when I'm testing at least I can check it every lap down the straight. Good luck looking in the middle of a race though, so I've got to get it right!!

Anyway, frustrated I got the machinist to supply me with a new 65sx piston and I'll be running it as a 69cc until I have firstly recovered financially and secondly got the heat under control!!!!

 

[ringo]

Nah plug chopped it first session to confirm that the airbox hadn't caused any lean running Mr67 and it was only a bee's whatsit lighter in colour!!!

 

[ringo]

I'm so in tune with stripping this damn engine now I can have a complete bike - piston on bench in 12 minutes!!! Not a record I'm too proud of!!!