YZ295 Hard Start/ Tough kick.

Hello I have a 05 YZ295 with very little time one it. The bikes in perfect mechanical shape, I put in a brand new crankshaft, crank bearings, crank seals as well as piston/top end kit. This has the Mo Betta porting with pump gas. This thing has a TON of compression, and is a bear to kick especially when cold. I have a fresh rebuilt 06 YZ478 and can start and kick that thing easily, starts up fine. I can kick 450's over cold or hot even on a hot stall with no problem. I used to play football and still workout, and can leg press a good bit of weight. So i'm kicking with a strong kick but its still tough to get started. Takes a hell of a kick especially when cold. Luckily I live at the top of a 200 foot hill, so I usually just run it down the hill to start it. Is this a common trait of the 295 big bore? I couldn't imagine the high compression race gas head.

Previously to this I had a 265 done by eric gorr and could start it pretty easily. Still tougher then a stock YZ250 to start and kick , but manageable. Started really easy when hot. Do other people have this issue with the 295? Cleaned the carb and verified its still stock jetting 178 main 50 pilot upgraded N3EW needle 2nd clip. Vforce3 Reeds. I ride in harrisburg PA, at sea level, anywhere from 60-100 degrees F. The rebuild didn't help or change anything with the starting issue. Runs great, power everywhere with a ton of mid and low, no sputter or hesitation anywhere. If its a pretty normal trait of the 295 I'm fine with it because I love the power. Just wanted to see if others had this same starting issue when upgrading to the 295? When you upgraded to the 295 from the 250 did the kicking strength go up as well? Was it tougher to start? Also what are others running for jetting at sea level?

I did some searching and theres not much info on 295 jetting compared to stock YZ250 jetting.

Thanks

Ryan

I just installed my EG295 low/mid top end last week and rode it this weekend. It is noticeably harder to kick. It's starts first kick, no problem, but I do have to give it a healthy kick. I'm about at the same altitude/temp as you, how clean does your jetting feel? I'm still trying to dial mine in.

Mine was really hard at first but within just a very few hours it was much easier. I also put a 4 stroke kicker on it,slightly longer but very little,best part it moves the kicker out slightly for a better angle,when i was having problems with mine it had super high compression and my foot slipped off and the peg got me good,had a big knot on my shin for about 3 months.

Good info on the 4 stroke kick starter. I will definately look into that if this doesn't get any better. The jetting feels OK, no hesitation or flat spots, and no pinging, but is tricky to start. I do want to do some plug chops and swap some brass to see if I'm missing anything. Really has no powerband, smooth bottom to top with no "hit", I'm really impressed with that. Air screw at 1 1/2 turns out currently.

It could just need some good break in time. I only have an hour on it now. Every other big bore I've done had some extra kick effort required, but this is more effort then those including a YZ85 112 super mini, YZ250F 290cc YZ450 478cc YZ250 265cc and now 295. This is a large big bore though 45 ccs extra, could have part to do with it. I'm re-valving a set of 07 YZ forks and shocks for woods riding, and will swap it over. It has really great MX suspension done my Axis on it now, its amazing for MX but Terrible in the woods, which is all I do with this bike.

Just remember there are 2 out put kicker shaft sizes,i built a 01 or 2 engine for my 04 which had a 4 stroke kicker,when i built the older engine first thing i noticed was how the 2 stroke kicker sucked,bought a 01 yz 426 for parts and used that kicker,instant help with that 295 motor. Maybe 03 or so up has a smaller out put shaft so just confirm size before a purchase.

Good info on the 4 stroke kick starter. I will definately look into that if this doesn't get any better. The jetting feels OK, no hesitation or flat spots, and no pinging, but is tricky to start. I do want to do some plug chops and swap some brass to see if I'm missing anything. Really has no powerband, smooth bottom to top with no "hit", I'm really impressed with that. Air screw at 1 1/2 turns out currently.

It could just need some good break in time. I only have an hour on it now. Every other big bore I've done had some extra kick effort required, but this is more effort then those including a YZ85 112 super mini, YZ250F 290cc YZ450 478cc YZ250 265cc and now 295. This is a large big bore though 45 ccs extra, could have part to do with it. I'm re-valving a set of 07 YZ forks and shocks for woods riding, and will swap it over. It has really great MX suspension done my Axis on it now, its amazing for MX but Terrible in the woods, which is all I do with this bike.

The 4ts have a automatic decompression lever on the exh camshaft that drops the compression to 115psi below idle rpm. That's why they are easy to kick over.

It should be about 12% harder to kick over from the change in bore size alone

assume 200 PSI compression on the YZ

250 piston has 5.62in2 =1124lbs at the rod

295 piston has 6.31in2 = 1262lbs at teh rod

Just put a 185 main and a 55 pilot. Throttle response much better off idle,sounds like its a tad fat at idle but can live with that if it stops the surging on chopping off throttle. Enduro next week so that will be the next real test.this thing just likes more fuel.

I'm going to try a JD blue needle and a 50 pilot to see if it cures my surging issue.

Just running stock needle in middle position,had a 48 and went to the 55, nice low speed improvement. Have a 8 slide and rb design carb bore and blade installed also.

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