Ok, after fitting RSE reeds we of course got like 2 weeks of rain. Today its finally dry enough 4 some riding. B4 fitting the reeds I was using 77.5 main jet (16mm mikuni) & running very well, so left that in. Strong down low but easily breaks into 4 stroking, more so as revs climb, so it'll b good 2 c how it goes when jetted correctly. Unfortunately, I wont have time til tomorrow afternoon 2 start on that. Cheers
reed kit
- Thread starter john8460
- Start date
Would be fun if you Aussies sponsored a Rock Solid reed valve race motor
and sent it to CA to race against the fast 2 strokes here on the track?
What do you think?
i know the guys at RSE build race motors of various types, check the top fueller on their web page. They do build motors for junior drags (not China girls). We've had good designers & builders here 4 ages, c the repco/Brabham F1 story, & Phil Irving designed the Vincent Black Shadow powerplant & planetry gearbox. The Sainty Bros 500ci SOHC 24 valve top fuel V8 is a cracker 2, Jim Reid said if it was allowed 2 run in the states he'd b breaking records, so yeah, ur right,,, it'd b good. After all, competition is where most advances r made. Unfortunately, I aint that financial. Cheers
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I didnt mean that 2 sound like I'm saying anything against u guys, we use alotta ur stuff 4 a reason, its good. We used the Buick V6 & Chev V8 in our Holden cars & love em. The 427 ci is a ripper. I have a Gibson Les Paul & ES335, plus a fender guitars & wouldnt b without em, the list goes on, so please dont take that the wrong way. Cheers
Hey Motorbicycleracing, ur idea has been playing on my mind all night. Like, if a group of us aussies each thru in a small chunk of change it wouldnt b hard 2 do, & u'd think the guys at RSE'd b into it. B good advertising 4 them & they've definitely got the facilities 2 screw a dedicated race motor & bike together. I've never checked out race rules there, but an RSE motor is slightly overbored to 70cc, I dont knowif that affects things, tho it'd b easy enough 2 overcome if nescessary. Food 4 thought. Cheers
The 2 stroke class has no modification limits on the motor except
that it must be based on the Chinese kit engine.
I guess the bottom line is that you must at least use the original cases.
There is no problem with 70 cc overbore.
Innovation is what it is all about.
If Rock Solid sends an engine or a bike I will give them a lot of
publicity about it.
The only other rule is no real motorcycle tires, moped tires are OK.
Must have working pedals and the fastest riders pedal their arse
off for any advantage they can get!
This is one of the fastest bikes.
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Damn, now you're talking. Why you been holding back the good stuff? lolThe 2 stroke class has no modification limits on the motor except
that it must be based on the Chinese kit engine.
I guess the bottom line is that you must at least use the original cases.
There is no problem with 70 cc overbore.
Innovation is what it is all about.
If Rock Solid sends an engine or a bike I will give them a lot of
publicity about it.
The only other rule is no real motorcycle tires, moped tires are OK.
Must have working pedals and the fastest riders pedal their arse
off for any advantage they can get!
This is one of the fastest bikes.
Yeah that is 1 wicked looking bike, nice Xpansion chamber 2. I've looked at a few of Arrow Cycle's producs b4, including reeds, a couple of pipes & reshaped heads. The guy definitely seems 2 know his stuff & does hi quality work. B good 2 c if RSE would b into that. I know they r very busy doing machining 4 large mining companies & the like, as well as developing other products, RSE being a venture they got into when Tony's young son got a Chinagirl kit. It would definitely get them exposure, u'd think. Cheers
Ok, so I went down 1 main jet size to a 75 & down from a 27.5 to a 25 (stock) pilot. Big improvement, noticeable gain in lower mid & mid range. Unfortunately I only got in about 20 minutes (wot with 2 guests with a 4 & 2 yr old boys visiting 4 weekend). A little fine tuning is still needed. The instruction sheet that came with the reeds say that the reed petals will soften after a short while of use so its gunna b good 2 c wot a fine tune & putting a decent few miles on it results in. Cheers
Hi Motorbicycleracing, another product I like from Arrow is the chain guide. Guys, if u remove ur sprocket/clutch actuator cover & look above the chain in there u'll c a large step in the casting. If u've ever heard a loud clunking sound of ur chain catching somewhere when its unloaded (if it has some slack in it), this is where its catching. This product from Arrow Cycles will eliminate this. Cheers
Still 4 stroking a bit, specially WOT. I'll go down to 72.5 jet. I plan on adding a bit more header length 2 bring the power down a bit, then add a little capacitance 2 the R/C timing network in the CDI 2 steepen the retard curve. This will (1) transfer some of the combustion heat 2 the pipe at higher rpm so the motor will run cooller there & (2) extend the "on the pipe" effect at higher rpm (as sound waves travel quicker at higher temps), to get back wot is lost from lengthening the header. Cheers
Ok, 72.5 main jet is good, needle clip in middle. Pulls well all the way thru with just a slight hiccup at about 1/3 throttle, but I havent done the air screw, just put 25 pilot in & left it where it was so that should clean it up when done. While discussing piston/port mods with fellow rider he showed me Jaguars page on reeds sugesting 5mm off both skirt & port floor, so I'll probly follow his advise rather than just taking 3 off both as I had planned. I'll put a few miles on as is first. Cheers
Ok, in a new piston I cut 2 ports, starting from 18mm from the top edge, extending down 17mm. Both r 9mm wide & I left 6mm between, for a total 24mm width to match the 3mm widened port. I also removed 5mm from the skirt bottom to same width. I had hoped to start on the cylinder over the weekend, but time didnt allow. Hopefully later this week. Cheers
Ok, its been a while, been busy then got laid up with a killer flu 4 few days but got the jug done. The boost port is cut at around 6 degrees from vertical, is 1cm wide @ the base & 8mm @ the top. I lowered the inner port floor 5mm by cutting @ about 9 degrees from vertical & radiusing into the floor so as 2 avoid lower crankcase comp ratio. both intake & exhaust ports had previously been widened by 3mm. So I'll get it back together & c how it goes. Cheers
Hi Venice, luckily I just remebered I was 2 measure how far the reed valve body protruded into the port & upper petal clearance 4 u. Ur right, it needs clearancing. They reach 7mm into the port level with manifold studs, 3.5mm thicknes @ end. With the steeply inclined port ceiling there's gunna b contact. I'll relieve it & blend it in & get back 2. I had planned on putting a lot more miles on it b4 doing piston & boost port mods, luckily, time didnt allow. I think u could fracture the upper petal with ease. Cheers
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Ok, to a depth of 8mm & width of 20.5mm I have cut the port ceiling horizontal. Care must b taken not to break thru the casting on the inner corners of this cut. I have then cut away @ 45 degrees the step created by the first cut, to blend it into the ceiling. This will allow the top reed petal a lot more clearance. I'll smooth it all really well. Now I dont have to worry about chipping the petal, or worse. Cheers
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Hi Ivan
How is the Aussie race bike challenge idea coming along?
Are you going to be ready for October 27th 2012?
Then there is the question of who is going to ride your bike?
Hi MBracing, its a real pity, but no one has shown ani interest in supporting this idea. I've been waiting 2 hear from RSE regarding new products with no luck. I had wanted a 70cc jug & ceramic coated slug. I'll keep doing development on this jug & piston then get the 70cc kit accurately machined to the same spec. This motor is the only 1 I have at the moment so, sorry. Cheers
Ok, the jugs all done, pistons on the rod. I slid the jug on & slowly cycled it thru a few strokes 2 make sure it's all good. No miscalculations with piston port timing. I have put aside time tomorrow arv 2 reassemble & throw in bigger pilot & main jets to ensure it starts out rich, so I can begin the process of correctly jetting to suit the 180 degree intake. I'll post results. Cheers