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Discussion Starter · #1 ·
Here is my problem. The CR250 intake manifold ESR sold me together with the Vforce3 does not line up with my air box boot on my stock 88 frame due to the extreme angle. The one I am holding is the stock one. I need to get this thing running by this weekend so what do I do?

Should I do a 1/4 inch spacer plate :blink: ? Get a UPP unit and pay 2 day shipping :angry: ? Or use my stock one and stretch the sh!t out of it
 

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If you have a spacer, you could try it. If not, what were you running before? If the length is right, you ought to be able to stretch the stock intake manifold to fit over a larger carb. A lot of guys have done it. You may have to heat it up.

I run the cr reeds and CR manifold with a 38mm mikuni tmx with airbox adapter ring. Fits perfect. ESR can also put the adapter ring on Keihns, but that won't have you running by the weekend.
 

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run the stock intake and heat it up in hot water to stretch it over the carb. after it cools it will hold shape and be easier to work with in the future
 

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Discussion Starter · #4 ·
Okay, this is really pissing me off. I tried heating up the stock unit and installed it. Now, the ANGLE on the carb is too high instead off facing outwards like the CR did. So I still CANT put my airbox boot. I have one last option available to me at this point. I will take off the 1/4 " spacer plate from my other motor/quad that I use with a CR rad valve and try that.

This is the first time I am putting a prox cylinder/spacer plate motor in a stock frame.
 

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I'm not sure what to tell ya. Here is mine. It's a pro-x with spacer plate, 88 frame, cr reeds, cr manifold, and carb with adapter ring. It fits perfect.


 

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Hey Norcal-

I had to run a 3/8 inch reed spacer on mine (I have VForce reeds, Pro-X cylinder with a spacer plate) and the CR250 intake wouldn't work. I had to put a new stock TRX intake and stretch the heck out of it to fit the 38MM. It will go. A new TRX intake will stretch much better- at least mine did anyway. But I still had to do some manuevering with the stock one too. You put the spacer plate on there and you'll need to do a little tugging, but it should fit and line up though, at least mine did anyhow. You should be able to see a close up pic of my motor in the photo section if it helps.

Hope you get it going.
 

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By the way. If you are heading to Pismo, ESR is real close to the dunes and they are sometimes there on Saturday. If you are still having problems or need more parts, they would probably be willing to help. Give them a call on Friday to see if they will be there.
 

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Discussion Starter · #10 ·
I am seriously losing faith in this project and am almost about to give up. I took the day off today just to tackle this issue. And here is what I've done so far.

1. 3/8 spacer plate + vforce+ cr intake = no go (angle facing out)
2. 3/8 spacer plate + stock reed + stock intake = no go (too high and tight angle)
3. shimmed spacer plate to 1/2 inch + stock intake and reed cage = still no go
4. used everything stock including carb = ONLY thing that works
5. vforce + cr intake + 38 carb + flex rubber hose (preformed radiator hose from Napa) = not enuff room
6. PHYSICALLY took the bike to a muffler shop to fabricate something similar to the flex hose above = not enuff room to put a hose over both the carb and pipe for clamping

Can any of you guys PLEASE post some close up pics of that carb adapter ring attached to your 38 a/s that ESR makes.

To be really honest, I never thought Id encounter all these clearance issues specially with a stock frame as I NEVER had these problems on my other JP frame. I even measured and matched frame angles to see if I had something bent. I even went as far as tilting the motor as far as it will go backwards to get even a small amount of space to work with.

BTW, how does that carb adapter ring attach to the carb ..... I assume a press fit maybe?
 

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The carb bell is machined down and the adapter ring is pressed on. I've never seen one on a keihn, but I know that ESR will do them. I've seen a lot of guys running vforce, stock manifold, 38mm carb, and stock airbox boot. How far off is it?

I don't have many close ups of engines, but here is one using a UPP manifold. It looks like the carb is not on there correctly in this pic. It's barely in the manifold.

 

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Here is one from one of our members. Did you try puting the spacer both in front and behind the reeds? That might make a slight height difference.

 

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Discussion Starter · #13 ·
The carb bell is machined down and the adapter ring is pressed on. I've never seen one on a keihn, but I know that ESR will do them. I've seen a lot of guys running vforce, stock manifold, 38mm carb, and stock airbox boot. How far off is it?

I don't have many close ups of engines, but here is one using a UPP manifold. It looks like the carb is not on there correctly in this pic. It's barely in the manifold.

Its off about 1/2" either way to make it even slip into the airbox boot. The adapter ring might help size down the opening of the carb a bit and improve the ENTRY angle than my stock TRX unit.

Needless to say, Pismo is getting foggier in the picture for me this weekend :( . I gotta work till saturday and dont know if I can get this thing together till then. Man, I can ONLY imagine fighting this thing :angry: when rejetting the carb during the motor break-in process.
 

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Its off about 1/2" either way to make it even slip into the airbox boot. The adapter ring might help size down the opening of the carb a bit and improve the ENTRY angle than my stock TRX unit.

Needless to say, Pismo is getting foggier in the picture for me this weekend :( . I gotta work till saturday and dont know if I can get this thing together till then. Man, I can ONLY imagine fighting this thing :angry: when rejetting the carb during the motor break-in process.

Can you run an air filter off the carb this weekend if you need to?

I have an orange UPP intake sitting around if you want it. PM me if so.
 

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Discussion Starter · #15 ·
Can you run an air filter off the carb this weekend if you need to?

I have an orange UPP intake sitting around if you want it. PM me if so.
I cant get anything to slip into the carb end bell due to the angle. I will consider that UPP manifold of yours also.

Im also thinking of using a rad valve with an extended (1" longer) radiator hose between the valve and the carb so I will have slightly more flexibility. How do you think its gonna affect the air/fuel mixture and powerband ? Bad idea :blink: ?
 

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Try this:

Put a cage on.

Get the hose ESR sells or the same dimesions. Put that over the bell and bend it in position. Zip tie that part to the frame.

Take your stock carb-2-airbox boot and hack it up, put a metal ring inside to prevent collapse, and hose clamp it up.

At this point IMO that is your best quick fix.
 

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Discussion Starter · #17 ·
Alright fellas, I got two different intake manifolds off ebay today. I am almost $180 deep on costs alone :angry: although I am hoping to forget all this once I get the quad going, hit that throttle and put that smile back into my face :p . I will update this thread for everybody's benefit as to which manifold works.
 

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Discussion Starter · #18 ·
This ONE seems to fit the best although I will do a leakdown test again since my intake gaskets have been crushed so many times and the clamps on the manifold hose makes for another leak/weak point in this whole set-up.
 
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