rmz290 big bore-first ride report

Had some time so I buttoned the 290 kit up tonight and took it for a rip. My spark plug boot was broken and I was going to wait,but then I decided to rob the one off my rmz450-it worked. Took a few kicks to get started. St the compression stroke it sometimes.is stiff. I expected this with a big bore kit. Once warm it starts in 1 kick but if you catch the compression at the wrong spot-its tough. When I first got on it-i could immediately feel more bottom end. The stage 2 hot cams make a little more noise than stock. Not a bad noise,just more valve train noise. Throttle response was just as good as stock. It spool up just a hair slower if pulling a taller gear. The bike has to be ridden exactly as it is-a big bore 250f lol. It still revs and feels like a 250f,just a lot more power and everything is happening at a lower rpm than stock. It has good bottom end,but what actually impressed me the most was the mid range. If you like strong mid range power from 6-10k rpm,this is it. Past 10k to the rev limiter,it pulls clean. Didn't really sign off or do anything weird just kinda hung with the same power from say 10k on. I was running a very rich map and had a quiet insert in the FMF 4.1. It will really be interesting to see how it feels when its properly mapped and has a free flow exhaust. So far I am really happy. It now has balls down low and an awesome mid range punch. My gripe would be the starting-my bike started effortlessly before the big bore and cams. Now I have to get the piston at the right stroke for it to be a 1 kicker-as it breaks in this may get better. Second gripe- if you lock up the rear wheel and dont watch the clutch-it will stall. No bump starting this thing-it will slide. Lastly, I felt the rear 250f wheel might be a little too small. I could feel the rear slipping more than before. I will try the Rmz450 wheel out. Gearing felt OK for now. A little too tight on faster parts of track. The trans didn't seem to like 2nd to 3rd gear shifts under load,which was not an issue before. As things break in and I spend some time,my opinion may change or I will find adjustments. After being off the Rmz for a couple weeks-my fork felt like a sledge hammer. Going to dig into the midvalve and soften it up a bit. Rear shock felt OK,but the rear tire wanted to slip too much out of turns to tell.

Cool stuff!  I like the report but think i'll stick the a 250 bore after reading this.  I like the dynamic of the standard plant but just want a bit more up top.

 

Interesting about the extra valve train noise.  I've just got the HC stage 2 exhaust installed for the moment and its certainly sounds different...tapping....sewing machine like!  Guys at the track last weekend thought my bike was ill! lol

 

Also i'm finding it's now harder to start....try the standard cams and see whats what i guess?

Had some time so I buttoned the 290 kit up tonight and took it for a rip. My spark plug boot was broken and I was going to wait,but then I decided to rob the one off my rmz450-it worked. Took a few kicks to get started. St the compression stroke it sometimes.is stiff. I expected this with a big bore kit. Once warm it starts in 1 kick but if you catch the compression at the wrong spot-its tough. When I first got on it-i could immediately feel more bottom end. The stage 2 hot cams make a little more noise than stock. Not a bad noise,just more valve train noise. Throttle response was just as good as stock. It spool up just a hair slower if pulling a taller gear. The bike has to be ridden exactly as it is-a big bore 250f lol. It still revs and feels like a 250f,just a lot more power and everything is happening at a lower rpm than stock. It has good bottom end,but what actually impressed me the most was the mid range. If you like strong mid range power from 6-10k rpm,this is it. Past 10k to the rev limiter,it pulls clean. Didn't really sign off or do anything weird just kinda hung with the same power from say 10k on. I was running a very rich map and had a quiet insert in the FMF 4.1. It will really be interesting to see how it feels when its properly mapped and has a free flow exhaust. So far I am really happy. It now has balls down low and an awesome mid range punch. My gripe would be the starting-my bike started effortlessly before the big bore and cams. Now I have to get the piston at the right stroke for it to be a 1 kicker-as it breaks in this may get better. Second gripe- if you lock up the rear wheel and dont watch the clutch-it will stall. No bump starting this thing-it will slide. Lastly, I felt the rear 250f wheel might be a little too small. I could feel the rear slipping more than before. I will try the Rmz450 wheel out. Gearing felt OK for now. A little too tight on faster parts of track. The trans didn't seem to like 2nd to 3rd gear shifts under load,which was not an issue before. As things break in and I spend some time,my opinion may change or I will find adjustments. After being off the Rmz for a couple weeks-my fork felt like a sledge hammer. Going to dig into the midvalve and soften it up a bit. Rear shock felt OK,but the rear tire wanted to slip too much out of turns to tell.

ac, bout time brothaaaa. jKing buddy.. nice report.. you mapped it quickly.... Is the mapping considerably different then your former mapping?

How does it sound out of the exhaust?

Cool stuff!  I like the report but think i'll stick the a 250 bore after reading this.  I like the dynamic of the standard plant but just want a bit more up top.

 

Interesting about the extra valve train noise.  I've just got the HC stage 2 exhaust installed for the moment and its certainly sounds different...tapping....sewing machine like!  Guys at the track last weekend thought my bike was ill! lol

 

Also i'm finding it's now harder to start....try the standard cams and see whats what i guess?

The 290 does take the 250f reel away a little. Its a lot stronger than the husky 310. Feels a lot like the sherco 300. It still revs like a 250f. I wanted a mini 450 and that's basically what its like. Its a very Torquey motor. The cam noise is exactly as you describe-sewing machine. At low rpm its not there,but mid rpm its noticeable. My kicker gets hard right at or before the decompress or kicks in. Almost like the decompress or needs to act a bit sooner. If I kick through smoothly-its no biggie. I also ride a rm250,so used to kicking that lately. As a stock 250f this bike kicked pretty easy. I remember my buddy had a big bore yz250f and was same way-if it Dont improve I will find a solution.I may try the stick cams for giggles.

Ac, I looked up that black opts ignition.. sounds sick, but meeeeen its expensive.. you broke it? Daaaang

ac, bout time brothaaaa. jKing buddy.. nice report.. you mapped it quickly.... Is the mapping considerably different then your former mapping?How does it sound out of the exhaust?

Haha. Haven't had time for much lately,but this has been killing me. I wanted to get it together so bad. I was around 12% richer across the board-so I am really rich. Now I will swap map plugs and work my way leaner till it starts to sing. It sounds much deeper. At idle it sounds like a 450 and then when on the gas just blipping around it sounds like a 250f. It lugs like a 450 and will pull a taller gear without any lag. Only rode for 30 minutes. Mostly just hitting this table top on my track and 2 straights. Tomorrow I will load up some different maps and take the sparky/silent insert out. I will really open it up tomorrow and see how it revs. I want to go over all the bolts and take a closer look at the decompress or and timing. I feel the tight exhaust clearance on the exhaust can hot cams recommends is partially the reason. Just a side effect of the grind IMO. They are trying to open the valve longer and farther and mapping tight to the can so it doesn't slam on closing so hard and pound the valve. I'd like camman to explain these cams a little. The design is different than most.

Have we got the "no-pulse" cam set.  Thought i read somewhere that they've moved away from this ramp design!?

 

Camman, it would be good to hear from you if your available at all?

Sounds like you got the best of both works now. Whoooo wheeee

Ac, I looked up that black opts ignition.. sounds sick, but meeeeen its expensive.. you broke it? Daaaang

I broke the stocker. Black ops coil will be here Thursday. That black ops coil is the real deal. I was skeptical at $220 that it would make an improvement. It was worth every penny. If it was shit I certainly wouldn't have bought one for my rmz450 and now my rmz250. It really does make the bike start better and run better. If you look at black ops design its really good. I feel its a logical upgrade,since an engines primary needs are fuel mixture,spark,compression/combustion. I should post a video of stock spark vs the black ops. Much brighter blue spark and more concentrated. I have no idea why suzuki went back to a standard coil and plug wire for 13. They said it was an upgrade. I Dont see it. I think it was a money thing.

I just may have to get one and take ur word for it.. btw: I checked on their website and they do NOT show that they offer one for a 2013 Rmz250.. does the 09'-12' fit the 13'?

Have we got the "no-pulse" cam set.  Thought i read somewhere that they've moved away from this ramp design!?

 

Camman, it would be good to hear from you if your available at all?

I know for a fact that I do. I got them used from evo industries (suspension/motor company) and they had them in a 11or 2012. You can kinda tell by the lobe. The backside looks almost undercut..at least to me. I think the cams are OK. I have heard people bikes after a regrind and they were pretty loud. As long as it works..

I just may have to get one and take ur word for it.. btw: I checked on their website and they do NOT show that they offer one for a 2013 Rmz250.. does the 09'-12' fit the 13'?

Have to contact them. They need to update site. There is a guy that sells them on ebay -kevin he knows all about them and gives great price. If you call black ops directly speak to chris. Search black ops ignition on eBay and even if model isn't listed-just contact they got it.

Messed with mapping. Went leaner and it was worse. I was at 5% richer. Now I am 15% across the board. I currently have the exp out and just normal clutch with HInson HD springs and plates. After 20 minutes,I could feel the clutch slipping. I thought it was slipping withe the exp core too. Going to try the z-start. Its next to impossible for a z-start to slip if gap is set correctly. I planned on selling it to a fellow TT member,but I think this is my only option. The bike is making really awesome power. At first it felt like a decent increase,but now that I am closer on fuel,it really feels strong. Plan on dropping a tooth on the rear. Maybe 2. Im really impressed. The hot cams are good and bad. Tried stock cams and it starts easy,but will not pull upper rpm as good as the hot cams. I am going to call them and see if they have any ideas. Bike does get hotter easier, like on the stand,but while riding no issue. I dropped the oil and it was clean-that made me happy!. Still a work in progress. Need to ditch work one day so I can get it just right. As it is right now-mapping could be improved,need stronger clutch (hopefully z-start solves this),need 450 wheel(got one),need easier starting(between hot cams input,black ops coil,ecu update and some tweaks) and better cooling ( might do Evans coolant or something else-right now just regular anti-freeze.

Interesting about the easier starting.  With yours is there a noticeable stiff spot, that if tackled normally (or as before with std cams) is virtually impossible to strike though sometimes?  This is what i'm finding.  Has to be the exhaust camas thats all i've installed and by the sounds of it you might be experiencing too.

 

Your mapping sounds interesting.  So every cell for every rpm range v throttle position you've gone +15%?

 

I'm playing with the idea of trying:

 

throttle opening percentage

10%  stock

20%  +2

30%  +3

40%  +4

50%  +5

60%  +6

70%  +7

80%  +8

90%  +9

100% +10

 

+ another couple of % from 9k up across the board.  Thoughts?

 

Also what poundage are your clutch springs?  I have three sets here +10%, +15% and +20% stiffer.  Your quite welcome to try them if you like?  FYI i have no experience with auto clutches and will not run them so can't really help there, sorry.

Edited by maximous35

Ac, for coolant consider bel-ray engine freeze.. it is a fantastic coolant..

Interesting about the easier starting.  With yours is there a noticeable stiff spot, that if tackled normally (or as before with std cams) is virtually impossible to strike though sometimes?  This is what i'm finding.  Has to be the exhaust camas thats all i've installed and by the sounds of it you might be experiencing too.

 

Your mapping sounds interesting.  So every cell for every rpm range v throttle position you've gone +15%?

 

I'm playing with the idea of trying:

 

throttle opening percentage

10%  stock

20%  +2

30%  +3

40%  +4

50%  +5

60%  +6

70%  +7

80%  +8

90%  +9

100% +10

 

+ another couple of % from 9k up across the board.  Thoughts?

 

Also what poundage are your clutch springs?  I have three sets here +10%, +15% and +20% stiffer.  Your quite welcome to try them if you like?  FYI i have no experience with auto clutches and will not run them so can't really help there, sorry.

YES! this is exactly what i am experiencing with the cams! i have a feeling they base the cam design on oem design. for top end you basical turn the cams away from each other for top end and bring them closer for bottom end. because of this,the decompressor is a hair late. on a stock compression bike-not a big deal. on a high compression or big bore,it will be noticeable. i have the hd springs from hinson they are much stiffer than stock. i tried stock springs and they were worse. i have some really heavy rekluse springs,but the pull is super hard. as for mapping-you can fill in all the blocks the same-your literally just making it x amount richer or leaner across the stock map. then i just swap in the different coupler to feel if i went the right direction. so far the more fuel i add the harder it pulls. i did try 30% that was too much. but did feel good at certain rpm. 3% is equal to a jet size. at 15% i am roughly 5 jet sizes bigger. now this is where it gets tricky. a strong engine may need smaller jets if pumping good because of suction on the carb. with efi we dont suck fuel we spray,so we have to add or take to get jetting right. tricky. i will get the bel ray. think i got maxima now.i never really had heat issues with a bike and not sure if i will now even,but want to have my butt covered. some things work great while testing but pop up as issues in a race..i dont want that. i wanted to race it this weekend but it needs more testing. going to see if i can buy a exhaust cam for the decompressor mechanism and modify it. didnt dig into it that far yet. ended the night messing with tps sensor. i was getting odd reading and couldnt get idle above 2600 even with idle and tps maxed out. may have a faulty tps.

Ok-rode for 2 hours. tried a bunch of maps found five percent across the board on the power commander to be the best with the rich coupler. Bike pulls really strong. I was finding myself in 5th gear wanting to pull another gear. The bike is fast. Really fast. I got the starting figured out. Had to try shimming valves tighter in exhaust. Went just a little tighter on the decompressor valve. Now it iicks easy. Tried so many maps but 5 per. With the rich coupler was perfect. First gear is useless. I will be dropping 2 teeth off the rear. The bike still revs. Not sure how other bb iits are, but my setup still makes its power up top like the stock power. The peak is a little lower in the rpm and it has 450ish bottom end. I can literally pull a wheely in 5th. Sometimes bottom end is almost too abrupt. But it transitions into mid quickly. Stiol being a small bore, its best to stay in the mid to upper rpm. No need to clutch. It pulls very cleanly. For startingif I go past top dead center and then start the bike it starts much easier. Starting in one kick is not an issue. It feels very kuch like the s tock powerband, just a whole lot more power. I originally thought it was running hot. Here I had a hose loose.oops.rookie mistake. It was dripping on header ane that's why I thought it was overheating lol. I'm really happy with this build. I had doubts and concerns in the beginning. After spending a good day with it- I'm really happy.

So did you go tighter on both or just EX-Left, and by how much, just the next tighter shim?  Didn't make anything quieter by doing so did it?

 

And ending up at +15% across the board made the best bang did it?  Didn't feel the need to make a tad leaner down low for more throttle response?

 

I will certainly be trying all this out.  The cam shim i can do in the garage but I'll have to wait for two weeks to get out to a track.

I have stock cams in. Hotcams are going back to hotcams. I will leave it at that until there is more to say. I am running u4 its an odygenated fuel, so my mapoing plus big bore could be way different from another's. I ended up 5% in some places 0 at some and 10% in others. Up top wfo I'm near 30%. I kept adding fuel and it just kept pulling. I could post the map. I need to snap some pics of the stuff inam talking about. I normally get on here on my phone, so I don't really think of it. Its busy this week for me but I will try to get more info up on the stuff.

I think a trip to PA is in order fellas.. TT ride at ACs house.   I want to try this thing out!   You have 15 lb on me and you have the RMZ450 and just reading all your posts from back when you got the bike have me really thinking. :thumbsup:

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