[riva]

Disclaimer- I sell carbs, pipes and camchain tensioners to dealers. I thought this would be ok here, if not, delete. I posted this a while back on another forum and the comments were mostly negative. But I don't think I've posted this here before. Anyway here goes..

We've got the 31mm CR's working pretty well with a full pipe. For fun we put HID's and a dark windscreen on too. We also test fit some 35mm flatslides if you want to get really crazy. Fitment on that one is kind of tight, it requires the use of a modified APE camchain tensioner. We messed around with stacks, filters, and swiss-cheesing the airbox for the 31's. Surprisingly we found all three are pretty close.

 

[hi-tech]

bigger the pipe the better air flow! vid on sound if u could

 

[spooph]

that's slick Riva! Yes, please, vids and pics of the bike overall, and maybe some flybys? I so want to do this to my bike.. But.. not yet

 

[riva]

I wouldn't run the 35 flats unless the motor has an extensively modified head but some people are doing it. The 31's feel great on the stock motor and will probably be the better choice even with mild head mods. Here is the accelerator pump clearance below with the flat slide carbbies. The tensioner bolt can be cut down more than shown here without effecting its function. We cut the nut off of the end and slotted it for use with a flat head screwdriver.

On that other site, the carbs were poo poo'd for being unnecessary. IMO the smaller the motor the more each of the extra horses is going to be utilized & appreciated. Do you really need more horses on a 1000? Really? Sure can use them here tho. Ok off my soapbox.. If anybody in socal has a completely stock bike I may be able to get my boss to allow me to borrow it for some side by side comparo runs before he gets rid of it.

 

[gummybear]

interesting... what kind of gains are we talking about here?

 

[Blue Ghost]

You mentioned mild head mods. Are there other mods in relation to the carbs and intake, like timing, valve adjustments or cylinder mods?

 

[Steezy McBreeezy]

I wouldn't run the 35 flats unless the motor has an extensively modified head but some people are doing it. The 31's feel great on the stock motor and will probably be the better choice even with mild head mods. Here is the accelerator pump clearance below with the flat slide carbbies. The tensioner bolt can be cut down more than shown here without effecting its function. We cut the nut off of the end and slotted it for use with a flat head screwdriver.

On that other site, the carbs were poo poo'd for being unnecessary. IMO the smaller the motor the more each of the extra horses is going to be utilized & appreciated. Do you really need more horses on a 1000? Really? Sure can use them here tho. Ok off my soapbox.. If anybody in socal has a completely stock bike I may be able to get my boss to allow me to borrow it for some side by side comparo runs before he gets rid of it.

A side by side comparison? Where in socal are u located?

 

[Blue Ghost]

Sorry, Maybe I should have been more direct in my question.
Did you have to polish the ports, bore and hone the cylinder, change the cam and lifters or modify the crank, change the stroke, piston and rings etc...? I surmise this is what you meant by head mods.
If you did, what were the specs when it was done and where did you get the parts?
Is there a video of the final product running correctly with dyno results?

 

[riva]

From our first run to the last we saw a difference of 33% in peak power. But the bike feels better everywhere not just on top. I live in West LA but what I'd love is a meet up at a drag strip. Not the 250R's forte for sure, but a timeslip is something more concrete than seat of the pants feel.

We didn't do anything to the motor. Its bone stock and the 31's work great with it. When I said head mods in my above post, I mean porting/valve work and cams/cam timing. The 35's are huge compared with the stock ports. You would need to have a pretty wild head to utilize the flow 35's would provide.

 

[Blue Ghost]

Thanks.

 

[riva]

Another thing is with the 35's the cable bracket touches the frame, but if you're serious enough to be using FCR35's you're probably not going to worry about tweaking the bracket a bit to get it to clear. BTW Both the CR31's and 35's can mount to the stock airbox. We pulled the airbox out of the frame for the velocity stacks and pod filters. I can walk anybody through how to get it out of the frame without destroying it if needed. After we tried that we were curious about how the stock box could be modified. So we shoved it back in to the frame then got a hole saw. We cut two large holes in the *back* of the box... you still have the stock filter doing its job this way. We drilled with the box inside the frame to make sure it was possible to do. Like I said, turned out the power is about the same with the drilled box as with the pods or stacks..

 

[Racer X]

I will be needing the 35s. PM me with your phone number .

 

[riva]

What about the 31's gave you fitment problems? Was it the cables or the airbox?

You can use the airbox or the stacks or the pod filters with the CR's or FCR's. The photos above show both the CR's and FCR's installed with the holed airbox. IIRC we drilled out two 2 1/8" (big) holes in to the back of the airbox. I personally would go with pods for simplicity's sake, but the power is the same any way you go.

 

[CSBrad]

Darkhorse you need to do a write up when you install these things man, you're gonna blow that record apart this year

 

[riva]

We can supply 39's too if anybody needs that much flow. I don't see how you could keep the bottom end together while making the kind of power that would warrant the use of 39's..

 

[riva]

BTW, Keihin makes 33's also. So 31's 33's and flatslide 35's and 39's.

If anybody wants to buy the test bike let me know. Its now for officially for sale in socal.