50mm bbk KABOOM!

[guen84]

whats your opinion baka??? you like ruima or malossi???
my main concern is the mini stroker heard some people say its a waste with the malossi, any thought on that??

[bakaracer]

I like both. malossi doesn't make a 50mm bore for dios so you cant compare. if a bore was not ment for a mini stroke crank then you have to check port timing and port to adjust which is why alot of huys say its a waste of time. its hard to get it to run right and good. the guys that say it runs good when they they just slapped the setup together is full of it.

[guen84]

well finally got it apart, TrafficJamz is the winner compression to high... burned a whole in piston... cylinder looks pretty good still.. possibly try one of limp's 51mm ruima kits now.. any one have some feed back on them over a Molossi kit..

if the cylinder walls are not scored up then just get another piston and rings. this time lower the compression even more. 93 octane will support about 9.5to1 compression on 2 strokes. if its higher than that then expect engine knock at high rpm's. Oh and the malossi or polini bore will NOT work on your block since you cut the boost port to fit the ruima one. you either have to fill it in with epoxy or aluminum.

ok well i guess that answers that question... next question my plug was white, but my jetting is huge 60 pilot and 160 main, needle all the way lean.. was it just from to high compression?? if it helps running a 8 plug

[bakaracer]

well finally got it apart, TrafficJamz is the winner compression to high... burned a whole in piston... cylinder looks pretty good still.. possibly try one of limp's 51mm ruima kits now.. any one have some feed back on them over a Molossi kit..

if the cylinder walls are not scored up then just get another piston and rings. this time lower the compression even more. 93 octane will support about 9.5to1 compression on 2 strokes. if its higher than that then expect engine knock at high rpm's. Oh and the malossi or polini bore will NOT work on your block since you cut the boost port to fit the ruima one. you either have to fill it in with epoxy or aluminum.

ok well i guess that answers that question... next question my plug was white, but my jetting is huge 60 pilot and 160 main, needle all the way lean.. was it just from to high compression?? if it helps running a 8 plug

yup!! like I always say on here, if the compression ratio is to high for the gas your using, no matter how fat you jet it, it will blow up unless you baby the throttle then yeah it wont blow.but holding it wot it will knock then KABOOM!!

[guen84]

well thanks baka for the help... i tell ya what, it sucked it happened but i was flying!!! gonna stick with same cylinder or get the ruima.. i was really starting to like my setup.. do you have any break in suggestions, im a fan of the NHRA way but didnt work out to good for me...

[bakaracer]

well thanks baka for the help... i tell ya what, it sucked it happened but i was flying!!! gonna stick with same cylinder or get the ruima.. i was really starting to like my setup.. do you have any break in suggestions, im a fan of the NHRA way but didnt work out to good for me...

heat cycles. at least 7 of them before even riding the bike. just let it idle on the center stand. 1st 150deg let cool to touch or around 80deg ,then 180deg, 200deg, 220deg,240deg,240deg,240deg. I cover the air inlet on the fan shroud or you can do it without the fan and shroud so it can get up to temp quicker.i set the idle around 2200-2600rpm

[kingkamehameha]

If your jetting skills aren't up to par then don't waste money on a expensive bore. Get another ruima and get the jetting right. If your doing your plug chops right then the wwhite plug should have been a red flag telling you somethings not right. You need to start with the needle in the mid and move it up or down one slot at a time. I would start with a 148 jet and move down a size at a time. You also may have had air leak from your exhaust gasket or something letting in extra air.

[Red Eft Performance]

With the mini stroke crank it Doesnt matter which bore you choose your port timing and compression is going to have to be addressed. Also like baka said its not the bores fault it melted its the tuner. The Ruima makes its power by having more displacement. The Ruima is also cheaper. The malossi makes its power with better efficiency from better port timing. The malossi cost more. is about 60$ more. Port castings on the Ruima are rough and the piston feels like its made out of lead. The port castings on the malossi are smooth the piston and rings are super light weight and high quality. You get what you pay for. Ive owned and run both of these bores(on stoke stroke) so these differences arent a biased opinion but differences anyone can see with the naked eye. Keith

[guen84]

If your jetting skills aren't up to par then don't waste money on a expensive bore. Get another ruima and get the jetting right. If your doing your plug chops right then the wwhite plug should have been a red flag telling you somethings not right. You need to start with the needle in the mid and move it up or down one slot at a time. I would start with a 148 jet and move down a size at a time. You also may have had air leak from your exhaust gasket or something letting in extra air.

the plug chop i was referring to its final plug chop... i started at 148 and ended up at 158, then changed to a 160 to be safe (haha)... air leak is deffinetly a possibilty, ive had the hardest time with this exhaust flange...

[guen84]

With the mini stroke crank it Doesnt matter which bore you choose your port timing and compression is going to have to be addressed. Also like baka said its not the bores fault it melted its the tuner. The Ruima makes its power by having more displacement. The Ruima is also cheaper. The malossi makes its power with better efficiency from better port timing. The malossi cost more. is about 60$ more. Port castings on the Ruima are rough and the piston feels like its made out of lead. The port castings on the malossi are smooth the piston and rings are super light weight and high quality. You get what you pay for. Ive owned and run both of these bores(on stoke stroke) so these differences arent a biased opinion but differences anyone can see with the naked eye. Keith

unfortunetly i screwed all of my fine tuned options up with boost port, dont want to risk fixing with epoxy.... so for now ill have to stick with large displacement.. you know what they say no replacement for displacement... my next build im deffinetly gonna try one these delicetly machined cylinders...

[bakaracer]

if the flange is not sealing good , you might have to use a propane torch to heat the j pipe and bent it some in the direction so that the flange will sit flat.on mine the the bottom on the exhaust side wouldn't seal to good so I bent the j in the direction need for it to sit flat.

[fastplastic]

this helps a lot too....

[guen84]

if the flange is not sealing good , you might have to use a propane torch to heat the j pipe and bent it some in the direction so that the flange will sit flat.on mine the the bottom on the exhaust side wouldn't seal to good so I bent the j in the direction need for it to sit flat.

thats exactly the problem ive had with 3 different pipes now... ive tryed vw metal gaskets some vw plastic gasket, homemade gaskets.... it would be fine for a couple rides, then id have to reseat pipe...little scared put ill have to give it a shot.

[guen84]

this helps a lot too....

do you got a link or some info on that gasket???

[kingkamehameha]

Does stacking base gaskets have anything to do with the exhaust flange not fitting properly? Your plug shouldn't be white with those huge jets and I'm surprised your bike even ran at all