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DRZ 470 build

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Planning on doing a DRZ470 build this winter for a friend of mine. Will be using the Hot-Cranks stroker + Cylinder Works BB.

The last DRZ I built was with a 440 big bore and I used a set of Hot Cam shafts in it. They dialed in okay but I was pretty disapointed with the performance gain. Yoshimura has a set of cams but the lift and duration specs look frighteningly close to the Hot Cams sticks. Kinda wary of buying them for this build.

I know Eddy used a set of RHC spec grinds from Web Cams but I'm really not looking for 60hp (45-50 would be fine).

Has anyone used the Yosh cams? What was your opinion. Unfortunatly, Megacycle doesn't have an off-the-shelf grind and I haven't seen any reviews of the non-spec grinds that Web offers.

The bike is probably going to spend its life off-road in the Western Colorado-Eastern Utah desert (I'm trying to talk him into a set of supermoto wheels too).

Any recomendations greatly appreciated!:bonk:

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Well, he wants a stroker, so I'm not going to argue with him on it. His big complaint is the soft bottom end power of the DRZ (complared to somethink like a KTM 525).

He really likes the DRZ, and would rather spend the cash to fix it up rather than buy another bike (he had a KTM and isn't about to buy another).

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strokers require special cams.

if you are only looking to make 50hp,skip the stroker.

When you refer to 'special cams' for stroker motors, do you mean cams with apropriate lobe centers for the combination?

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you need the rhc cams.the hot cams and yosh cams do not have enough duration for the stroker motor.you could use them but youll need 100 oct fuel to prevent detonation.

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you need the rhc cams.the hot cams and yosh cams do not have enough duration for the stroker motor.you could use them but youll need 100 oct fuel to prevent detonation.

Even if I move the intake lobe center farther down the bore? (reducing dynamic compression).

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From what i understand hotcams don't have enough duration to bleed of the required amount of compression that is needed for a stroker.

Many people find that they have frequent headgasket issues when using hotcams in the stroker setup.

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So your looking for hi torque and low Hp. ??

Use the 39fcr , average flowing pipe, like FMF or Akropovic, ,stock valves..

Cams?.

I would talk to Eddie about doing a set of cams to suit you application...

Hotcams would work, but will increase the odd's of pushing the head gasket (not recommended):banana: or alternatively you could lower your compression...(not recommended):busted:

Personally I would go for the 60HP stroker, you are going to bring along lots of torque to go with the HP...:bonk:

You could have adjustable cam gears fitted to the 187 cams and dial them in for mid range, (retard the intake ,advance the exhaust)...(Recommended):smirk:

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i think once you research and explain to him what it takes to build a stroker properly he may change his mind.

doesnt matter what you do with the lobe centers of hotcams,they are not suitable.

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Had a little chat and it went like this; I wan't my DRZ to run like a KTM 525.:bonk:

Since I'm trading my labor for his (he owns a transmission shop and I need a tranny built for a Mustang) and we both can get parts for dealer cost, money really isn't an issue.

So, running with that, anyone have any suggestions on build details? I'm sure he's not going to complain about 60hp, but I don't know what to expect for reliability from any combo that packs that much punch. He is a fast rider (was racing A class a few years back but his business hasn't allowed him to ride as much now).

Appreciate the comments guys!

Hey Eddy, you might remember me from when you worked at the salvage yard. Always looking for stuff for vintage racing. Been living on the Western Slope for about 12 years now.

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what pipe does he have? carb?

The bike is a 2006 E model that's pretty much bone stock, save for an old FMF slip-on and an Acerbis tank.

The bike is hammered shat-on-a-stick (sorry to say, but he did get his moneys worth out of it)

It'll need a pipe/header and I'd like to ditch the slant FCR for an FCRMX. Like I said, this is a total, from the ground up build.

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Sounds like it's due for a full rebuild anyway...

I would just email or call Eddie directly, he will fix you up with the good bits,41 Fcrmx, SSW/MRD, +1mm valves and spring kit....etc....:smirk:

BTW..I would send the head to the Master for porting to suit the larger valves..:bonk:

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i would not be happy with that result

you need to pull away ... on one wheel :bonk:

:smirk: I felt pretty good about it! I had the pipe corked at the time...

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