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2012 RMZ450 hard to start/under powered?

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I have a friend who bought a 2012 450 over the winter. Right from the day he got the bike it was hard to start. Im talking 15-20 good top dead center kicks every single time. Then I rode the bike. I have owned and ridden a lot of 450s and this is by far the slowest 450 I have ever ridden (maybe slowest bike period). It really just has no bottom end at all I even tried using first gear through the corners. Something is obviously wrong, but he just cant figure out what. Valves and timing have been checked and are perfect. He switched tanks with another Suzuki thinking it may have been a clogged fuel filter. Still no better. The weird thing is the bike runs clean. Doesn't pop or bog or anything it is just slow and won't start. He did say the last time he took it out it was stalling in corners some. Any ideas????

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How many hours on bike? Do a compression test on the bike. Next up would be testing the electrical components. You could also run a diagnostic to see if there are any faults. The manual explains how to do it. If you don't have the manual I can try to scan mine for you.

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I would say he has 10-15 hours on it but no hour meter so not sure. Also not sure if he checked the compression either. I would think if it was electrical it would be running poorly or even cutting out sometimes? Or is that not necessarily true? The bike has done it since brand new but he says it has been getting worse as of late.

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make sure the hot start has some play in it.its a new bike,probably something simple.

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Its a suzuki.  It has a linear powerband that the fast riders crave however the novice and beginners do not like as its not interesting and very predictable.  Its totally normal and it makes more power than you may think ie 55 hp and is only topped by the ktm which has 57 hp.  I like power because its usable and when you lean it over it doesnt pop up and get crazy,  mainly it even better because there is no crazy power surge and it is quite fun to use if you know what I mean.  

One thing you can do to wake it up a bit is the air filter cage is really restrictive so you can buy the 2 stroke one and it will help out a little bit and its only $15 and the next step is an exhaust which makes a more notable difference and is very noticeable,  however to take full advantage of both mods you should have the bike remapped.  I mean yes you can do both and it would help a lot but to take full advantage of the mods you should get it remapped.

 

In the end though it will never hit as hard as a yamaha or a kawasaki,  which is not a bad thing as it puts out more hp and since it doesnt spend the whole time spinning the back tire which means your spending more time going forward.  This trait is probably why its a popular bike with the pros and some b riders but the others like you want a hard hit I would say stay away from honda and ktm as well as the motor characteristics are close to the suzuki as they have a smooth power delivery. 

 

You can always get a 250 2t if you want a challenging powerband to ride.

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I would say he has 10-15 hours on it but no hour meter so not sure. Also not sure if he checked the compression either. I would think if it was electrical it would be running poorly or even cutting out sometimes? Or is that not necessarily true? The bike has done it since brand new but he says it has been getting worse as of late.

Oh ok, I thought maybe it was a used bike... they can run like they are under powered and be very difficult to start if there is a fault. It doesn't necessarily mean that a part is bad. Just that it is not operating properly. It does not have to cut out or run extremely poor for that to be the case. Its cheap, simple and would be the first thing I would check. Just my .02. Electrical issues can be extremely weird and hard to diagnose.

 

Just as an example, my last bike had increased resistance in the coil and it only ran bad about every 5th time I tried to ride it. Wouldn't idle, poor acceleration, cutting out etc. then the next time I would go out it would run perfect. Finally traced it to the coil after measuring resistance in all the electrical components and never dealt with the issue again. Luckily on the RMZ there is a light that you simply plug in and it will tell you exactly what is wrong through a series of flashes. Kinda like Morse code.

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Ringo, I have owned every brand of 450 besides a kaw and have ridden them all. Trust me when I tell you it isn't just the mellow power of a Suzuki. There is a problem. He has put an exhaust bigger sprocket remapping thing from yoshimura. No 450 with a pipe and a bigger sprocket should or would leave you wanting more power.

Bdubb I think you're right need to check the codes on it. I guess for some reason in my mind I was thinking of a short or something when thinking electrical so I had kind of ruled that out thinking the bike wouldn't run clean.

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Ringo, I have owned every brand of 450 besides a kaw and have ridden them all. Trust me when I tell you it isn't just the mellow power of a Suzuki. There is a problem. He has put an exhaust bigger sprocket remapping thing from yoshimura. No 450 with a pipe and a bigger sprocket should or would leave you wanting more power.

Bdubb I think you're right need to check the codes on it. I guess for some reason in my mind I was thinking of a short or something when thinking electrical so I had kind of ruled that out thinking the bike wouldn't run clean.

You mentioned that he is running a fuel mapping system on the bike... I would try changing the map to see if it helps at all. I've seen a few buddies seriously jack up their maps. Probably even easier than reading those codes.

Edited by BDubb106

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He tried the mapping thing to fix the issue. It was like that before he put it on there and got no better after. The day he got the bike it was slow and wouldn't start. He probably should have taken it right back to the dealer but didn't.

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He probably still could. They will likely run the diagnostic for him and let him know exactly what is going on with it. He should def. call and ask. That will at least tell you where the issue is.

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