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Hi all,

New to the DRZ community though I have 5 friends with them.

Here's my story:

Just picked up a '06 DRZ400SM and need some sage advice from the gurus here.

It has Yosh cams, full Yosh System, Thunper Racing 470 kit, stock carb with 180 main, clip #3, not sure of the pilot or A/F screws (it's all written down on paper I get monday) on Thumper kit, stock CDI.

There will be a Yosh box on it.

I know that the FCR is likely the way to go ultimatley, but wonder what settings the stock carb should be at for the current configuration?

I don't think I have the 3x3 mod, need to look up the specifics of that.

Does anyone have the spring rates for the front forks and rear shock and could they make a reccomendation for a 215# rider with a pro roadracing experience? Does Ohlins make a shock for this thing?

Thanks in advance for the guidence!

Tony D

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what stock carb?

theres no way the stock BSR mikuni has a 180 in and runs at all.

TR 470 kit...............bad idea.sounds like it wasnt build by informed people.

you cannot run the yosh cdi with out at least installing the spring shims that cam with the yosh kit.

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Really the best thing is to tear it down and start from scratch. Most of it is useable but needs to be set up right. You sure it is the stock carb? 36mm BSR Mukuni? Big black top? Who would build a 470 and use the stock carb?? Maybe the FCR was taken off and sold separate and the jetting you have is for a carb you do not have?? Anyway, 180 is too big regardless. Look at the top of the air box under the seat. Is the hole 3" X 3" more or less? Has to be. Who would build a 470, use the stock carb, jet it 180, and not cut out the top of the air box? Does this thing run at all?

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Yes, he said he didn't get the Yosh CDI to work with it.

My understanding is that the stock carb has a thumper jet kit in it for the 470 conversion.

Yes it runs "fine" aside from a little fluffy (?) on top.

"TR 470 Bad idea" Could you explain?

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Yes, he said he didn't get the Yosh CDI to work with it.

it works,he just didnt know how.you have to cut the green at the big plug in the cdi.

My understanding is that the stock carb has a thumper jet kit in it for the 470 conversion

either someone is confused or it doesnt have the stock carb on it.

the stock bsr carb wont even begin to rev with a 180 main jet.

Yes it runs "fine" aside from a little fluffy (?) on top.

regardless of which carb it has,180 is way way way to rich.

"TR 470 Bad idea" Could you explain?

2 things.one is the bore is way to close to the water jacket now.they tend to have head gasket sealing issues.

the other is its a iron liner.in one step they took your motor back 20 years in technology.

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Okay guys so tell me how to optimize what I've got here.

Lets assume I'm keeping the 470 kit in it for starters.

I heard of a couple head gasket issues from the liners being set to high, but Thumper is aware of that and they did mine recently so I'm hoping that isn't going to be a factor.

From that are the Yosh cams fine?

Is there a usable setting for the Stock carb in the interim?

I assume the 3x3 mod is for a FCR as well when I get that so I should just go ahead and do that?

I can use the Yosh box and Eddie just gave me the secret to making it work. It sounded like I need to keep a mind on the revs without special valve pieces?

Thanks again in advance for the insight everyone, I really appreciate it. :thumbsup:

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From that are the Yosh cams fine?

yes,they are fine.just not earth shattering gains.

Is there a usable setting for the Stock carb in the interim?

yep,3x3 mod,dynojet kit for the stock SM carb.

155 main jet

dj needle

needle clip 2

dj slide spring

25 pilot jet

2.5 turns fuel screw

I assume the 3x3 mod is for a FCR as well when I get that so I should just go ahead and do that?

stock carb or fcr.still needs 3x3.

the fcr carb should have come way before motor mods.

I can use the Yosh box and Eddie just gave me the secret to making it work. It sounded like I need to keep a mind on the revs without special valve pieces?

the yosh kit came with spring seat shims.you must use them or RHC valve springs.

with that 470 piston,theres no need to rev it that far.its falling off the power way before the rev limiter.

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Hey Tony,

Randy here, get together with Burned ( ED ) he's the local MONDO GURU, and most everyone here truely takes his words to be true.

There's a couple others as well, you'll just have to weed thru the info as it comes in. These guys are great, and helped me get Leah's bike going piped and jetted in 1 thread.

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RW, I believe, that's why I'm here.

Ed, would you say there is no real reason to use the Yosh box with the 470 or is there some benefit to it?

Looks like I'll either be buying the carb set-up or rejetting soon.

I'll report tomorrow on the actual carb settings to give a better picture of where it's at.

thanks again,

Tony D

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Okay, it has 4x4 mod and a DJ kit with a 180 main. :ride:

I guess it doesn't matter as the FCR is on its way! :thumbsup:

Glad I got a hold of you guys before running it further! :applause:

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Okay, it has 4x4 mod and a DJ kit with a 180 main. :ride:

I guess it doesn't matter as the FCR is on its way! :thumbsup:

Glad I got a hold of you guys before running it further! :applause:

i cant believe it revs at all.

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Do not trust Thumper Racing they destroyed my motor they do not know

what they send you :ride:

I did not have any problems with my YZ 470

but my KTM is a nightmare now

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Okay guys so tell me how to optimize what I've got here.

Lets assume I'm keeping the 470 kit in it for starters.

I heard of a couple head gasket issues from the liners being set to high, but Thumper is aware of that and they did mine recently so I'm hoping that isn't going to be a factor.

incorrectly installing the steel liner is just one screw up.

Using a steel liner is the bigger screwup.

Regardless of the liner material, the bore is too large for reliability. To expect it to work for awhile you

Must use a quality, correctly sized head gasket, coated with 2 coats of copper coat spray. Tq clean, lightly oiled head bolts using oem steel washer and final tq of 43 ftlb

I can use the Yosh box and Eddie just gave me the secret to making it work. It sounded like I need to keep a mind on the revs without special valve

The box provides no performance advantage , likely is is a cheap copy of a yosh cdi, not a real mistubishi made cdi.

To use any higher revving cdi with stock springs, us have to shim the springs.. And then, you will see spring failure at some point.

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There's noe reason to rev beyond the current limiter, the power is fading long before the rev limiter kicks in.

If the bike has the oem bsr carb and a 470 kit, something is not right..

Check if there's a spacer on the bottom of the cylinder, guess people tend to make a short when selling a bike.

The yoshi cams are ok, like the hotcams, but over priced like all other yoshi stuff.

Don't think these cams are the best choise for a 470cc, but ...

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Check date

I did, today at 1223 a user brought this old post back to life,, as such it was visible to all on the front page, so a current comment about an old issue to make current clear recommendations available to anyone that read this resurrected thread was made.

:ride:

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That TR470 kit ended a TAT ride I had planned for a year. Did ok in CO but as soon as we dropped down into Moab it was pinging/knocking like crazy. Long story short we went home 4 days into the ride :lol:

No surprise, the engine was redone with a CW 434 kit and now runs stronger and better than with the TR470 :ride:

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