cRanbrook build



Street Ryderz

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Oct 14, 2016
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Hey gus, what do you think about downsizing the carb from 26 to 24mm? It had pretty good torque and great top end with the old pipe. Looking to get better throttle response and maybe a little more mid range. Also, what about a power jet? Would that help keep topend?

@Street Ryderz @gary55 @FNTPuck
Going down from 26 to 24 may make it a bit more responsive,but on big reed blocks I dought it!The power jet is handy at the top of the pipe to help the engine not go to lean if you're able to over rev.
 

FNTPuck

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Jul 2, 2018
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Never ran a carb that big on a chinagirl so can't help ya with any first hand experience - @Street Ryderz would be the one to ask. 26mm does seem awfully large for a chinagirl though, and the larger the carb the lower the velocity at low RPM (which is why big carbs need larger jets than small carbs for the same combo to not go lean, not enough suction to pull the fuel out).

Most of my time has been spent on 4strokes lately, although I did do some maintenance last weekend on a fun little 2stroke Blaster quad with a 240cc big bore kit for my nephew. Was surprised that little thing will wheelie without clutching it up, just throttle!
 

Spare_Parts

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Nov 29, 2017
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Went ahead and ordered the 24mm, jets, clear float bowl (had problems with float height last year) and a Stage6 mixture knob from treatland.tv.

Now I'm thinking of downsizing the intake id to something closer to the carb size. Right now it's 35mm, same as the od on the carb flange. Last year it was 30 or 32mm.
 

Street Ryderz

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Oct 14, 2016
Messages
2,951
Went ahead and ordered the 24mm, jets, clear float bowl (had problems with float height last year) and a Stage6 mixture knob from treatland.tv.

Now I'm thinking of downsizing the intake id to something closer to the carb size. Right now it's 35mm, same as the od on the carb flange. Last year it was 30 or 32mm.
Yeah idealy you want the whole track matched up on a piston port engine to maintain nice constant velocity,the reed blocked engines have larger intakes trying to get the same volume at a lower velocity using the big carb.The only real advantage I've seen to the reed is the lack of back wash and not loading up as much driving around just off idle,I can see where in a high rpm 2 stroke that spends it's time at 12-14k or more it being useful in that sence but also can see how it too would have it's restrictions.
 

Spare_Parts

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Yeah idealy you want the whole track matched up on a piston port engine to maintain nice constant velocity,the reed blocked engines have larger intakes trying to get the same volume at a lower velocity using the big carb.The only real advantage I've seen to the reed is the lack of back wash and not loading up as much driving around just off idle,I can see where in a high rpm 2 stroke that spends it's time at 12-14k or more it being useful in that sence but also can see how it too would have it's restrictions.
So do you think it should be downsized? Sounds like it will be fine for the reeds.

Got a shipping notification from usps, carb and the other treats will be here Monday! I love those guys at Treatland! They know how to run a business. Now if we could get them to sell cg parts....
 

Street Ryderz

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Oct 14, 2016
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2,951
So do you think it should be downsized? Sounds like it will be fine for the reeds.

Got a shipping notification from usps, carb and the other treats will be here Monday! I love those guys at Treatland! They know how to run a business. Now if we could get them to sell cg parts....
I would still want the intake's id to be matched to the carb if at all possible.
 

Spare_Parts

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Nov 29, 2017
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1,167
Just tore down the engine and the bottom end is in great shape. Bearings have 0 slop, seals are pliable and smooth and the big end bearing is good. The crank is only balanced to the rod. It is drilled to oil the seals and guess that works. The little bit of carbon wiped right off of the head. Some blow by on the piston but nothing to worry about. Cylinder looks good. Going to keep the top end for a back up. Oh, the clutch looks great. Adjust it right and they last.

Have to clean and strip the paint from the case and then paint the engine components. Super excited! It's getting close to going together finally.
 
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