Re-jetting my 09 DR650

[tobster]

Hi, I just bought an 09 dr650 and id like to get a bit more power so was going to get a jet kit installed, airbox drilled, baffles drilled out. Im not hugely mechanical (code for fairly crappy) but Im sure I can do this myself. Dealer says he wont warranty the bike unless he does it. Ive just had my bike back after its first 1000k service with this dealerand he didnt do a good job, bike was missing a few nuts, seat wasnt fitted into top bracket and the fork seal protectors were damaged. Im pretty pissed about this as it took them a whole day to make this mess and cost me $300:mad3:. Needless to say I wont be going back. So I was wondering, can anyone recommend a good shop to make this upgrade for me, im in maple ridge but dont care where I have to go, just want a quality mechanic that has some pride in his work.

If there are any big downsides to re-jetting please give me a heads up.

Thanks, this forums great, seems like a really good bunch of people

 

[franhoser]

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Tobster,

Here is a re-jet video for the drz. It's virtually the same carb on the dr as shown here. The air box on the dr is difference

http://www.youtube.com/watch?v=VtKWbs0N5lo

Rejeting won't gain you much power as you think but it does give you better throttle response.

I've re-jetted both a DR650 and DRZ and every time the hardest thing to do was getting the carb out.

 

[old trials guy]

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My recommendation is to keep it simple and do the three following mods to improve fuel metering:

1) Remove the snorkel (do not cut holes in the air box as it really only makes it noisier)

2) Remove the carburator and remove the brass plug that hides the air mixture screw. Easiest way is to drill a hole into the plug (the plug is about 4 mm thick) and tap in a drywall screw or self tapping sheet metal screw and pull out the brass plug. Now you can adjust the mixture screw.

3) Remove the slide and needle. To do this you will need a very good Phillips screw driver as the screws are tight from the factory. Be careful on to strip the heads. It's helpful if you have friend to hold the carburator firmly while you remove the screws. Once you have the slide out remove the needle and find a small spacer washer to go under theneedle (you may need two small 4 mm washers or something that fits over the needleandinside theslide needle hole. You need about.030 to .040 inches of spacer. Thishas the same effect as changingthe clip position on a carburator that has a needle with circlip. You are raising the needle up which will richen the mixture just offidle where the stock bike typically stumbles and hesitates.

This is the poor man's solution but works really well without changing anything that can't be undone or returned to stock at a later date.

Good luck with your tuning.....otg

 

[tobster]

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Thats good info, thanks, Im going to watch the VDO a few times and then have a go, doesnt look to difficult, im suprised you said the power increase wasnt significant, Ive heard from a few people its a huge improvement. Guess its all relative.......thanks again

 

[tobster]

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Thanks Old Trials Guy, I already bought the jet kit, else I would try your suggestions there, would you drill out the baffles in the exhaust as well? or is that not necessary, im a bit worried about it sounding like an angrytractor and giving my neighbours a hard time, thanks for your reply.

 

[Buck]

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tobster wrote:

im suprised you said the power increase wasnt significant, Ive heard from a few people its a huge improvement. Guess its all relative.......thanks again

The jet kit (or shimmed needle) alone will not add much of a power increase but as was said will eliminate the lean bog off idle, surging at cruiseand improve throttle response.

To get the power increase you gotta go the full route.... meaning open up the breathing in and out.... Open airbox, jet kit, high flow air filter, free flowing exhaust.

 

[tobster]

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thanks, I suspected that may be the case. Thats basically a stage 2 upgrade (or at least in car terms anyway). Im just concerned about whether or not it will affect the reliabilty of the engine? or lead to future problems with other parts being put under greater stress etc, there always seems to be a price to pay when deviating from stock.....

 

[Cedartree]

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I agree with your worries about long term durability after mods. The only thing thatI have to offer is that the manufacturers mustcomply with EPA or other emissions legislationand tune the engine as lean as possible to comply with those limitations. I've done the 3X3 mod and JD jet kit and so far have noticed a pleasant improvement in throttle response andnot much in power. Throttle response is better than power when you're just going to make minor changes like I have. I would go further down the mod road but that means a louder pipe and the neighbors might not appreciate it as much as i do...

 

[RobboDosing]

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I used to have a jet kit in mine but returned the bike to stock after about 6 months. The gain was pretty marginal (a bit more low end snap) and it took a hit in fuel economy and I like having more range. I used Mspeed and Modern in Van but any shop with an actual mechanic in the staff ought to be able to do it. I've done the job myself and it's pretty easy for a careful non-mechanic.