The RSE reeds are very good for the normal rev range or a little above & if u do the nescessary portwork u'll get a decent torque increase (very noticeable, right thru the rev range). U'll have to do a little intake port work on the jug (cylinder), but most importantly, u'll need to cut a port in the intake side of the piston to allow it to intake thru 180 degrees which is the whole point of adding reeds. I gave all the lowdown of how I did this, with measurements etc in another thread a while back (I'll find & steer u 2).
I'm not familiar with the CNS carb but know a lot of people use it.
An upjet means going to a larger jet to richen up the mixture due to reduced intake velocity. To give u an idea, I use a VM16 Mikuni carb. The jets are sized in increments of 2.5, which I think is just a numbering system, not a measurement.
B4 the reeds I was using a #25 pilot jet & a #77.5 main jet. After adding the reeds & porting for, I needed to a #32.5 pilot jet & a #100 main jet to get the mixture right. Without the reeds & piston port the motor wouldnt run properly with this jetting, it would be f¤ck¤n miles too rich. I think reeds work well with a jackshaft as having gears negates the need for hi rpm. Torque increases are of more benefit to u. These motors are very poorly ported, but the ports are arranged to give power in the lo & mid range, which again suits a jackshaft/geared setup. Knowing how to properly port a motor to move power delivery to another rpm range really is a bit of a "black art". If u dont really know wot ur doing in this regard, maybe its better to leave the power band where it is & boost it with (A) a port match job. (B) a better intake manifold (straight), carb & aircleaner, & fuel petcock. (C) a tuneable expansion chamber. Dont underestimate one of these. SBP offer a good one that is well worth getting. (D) a hi comp head (with squish clearance properly set, 0.030"). Upgrade ur small end bearing to a better quality, 15mm wide one b4 u do this.
If u do these things (I would also recommend an adjustable CDI) & ur pipe is tuned to where u want it (mid range), & ur carb is properly tuned, u'll have a good performer & have learned a bit about working on, tuning etc ur motor. If u still want more torque, then add the reeds. Just my thoughts. Also, its a good idea to replace ALL fasteners with automotive grade ones, socket head types where applicable, especially the mounting ones (where the motor mounts to ur frame, tho the rear should already be done from ur jackshaft) & the head/cylinder studs & nuts (use flat washers). Hope this helps. Cheers
Edit:
See the thread "Reed Kit" in this section where I went thru the whole proceedure when I added the reeds, includung a descruption of all the modifications I did to fascilitate maximum intake duration, including measurements. I also go thru the upjet which was more than I anticipated. I first just added the reeds (without mods) which required a small downjet due to eliminating blowback & felt just a tad stronger,,,, and then had at it to do it properly. Hope this helps. Cheers
