Messages

SoCal hit it on the head!!
Lyn

You would have better luck with a stud remover.  I have two, one a Craftsman (I think) and one a Snap-On.  For a case stud the Craftsman works better because it can get right down to the bottom of the stud and the Snap-On works at the very top and I have had that one break studs which is a PITA.  The Craftsman style has a large metal
section that slides down over the stud and an inner section that turns and engages the stud when you put a rachet or breaker bar in place and apply pressure.  (Lousy description, I know.)  Best thing about that one is that you get right down at the bottom of the stud and eliminate any weakness in the rest of the stud.  I have had good luck using a 3/8" drive air wrench set at low torque hitting the stud for a couple of minutes and working it loose.  Good luck.
Lyn Garland

Depends on what you want the bike for.  R5s are nice bikes but piston port engines are not as tractable as reed valve engines and that's why a lot of guys with R5s or DS7s changed their top ends to RD 350 or 350 cylinders; better around town manners.  That's why all my street bikes have used OEM pipes and the race bikes, except in the production class, had chambers.  Using the OEM exhaust lets you keep the center stand also and you only lose a little cornering clearance. 
Lyn Garland

Wossner sells RZ pistons sized 64.19mm and 66.44mm.  I don't know about Wiseco but I think they sell 65.00mm pistons also.
Lyn Garland

A few years ago I asked Kevin Cameron about the rumor that you should use green locktite on the OD of the inner bearings you used that did not have anti-rotation pins installed.  He replied that he and Erv had tried that and upon disassembly found absolutely no indication that locktite had been used and therefore it was his opinion it was of no value.  The bearings used in the crank rebuild were Koyo 6206NRC3 obtained from a reputable dealer.  They were used because the OEM bearings were out of stock and on back order from Japan with an expected fill date of six months.  I always use OEM bearings and seals whenever possible, but I have used these bearings in the past and have never had any problem with them. 
Lyn Garland
PS:  Koyo bearings are made in Japan

Somebody described a method to check your main by backing off the throttle a bit at WOT, but I cant find it now. Anybody know what it was?

I mentioned that several years ago as a tool we used to check our main jet size.  It works because the Jet Needle reduces the flow of fuel through the Needle Jet more than the air is reduced by slide closing the carb venturi.  Now, there are a couple of things to consider: We did this at the race track and it was after the engine had been run a few laps so that it was good and warm and all residual fuel/oil was cleaned out of the crankcase.  The throttle was closed only slightly, just a touch.  I can't quantify how much, just ease off a bit and check for a reaction.

After that and during our tuning progression a group of five of us bought a used Patrako water brake dyno.  Kept it at a friends plant and used it for a number of years.  It was quite old fashioned, no exhaust diagnostic sensors, just torque and HP meters. (The HP meter was suspect.)  We used the bike Tach and the dyno torque meter to calculate the horsepower, which was farcical, but we could produce a curve and we could always compare one curve to another.  A great tuning tool and we had great luck using it.  The group finally reduced to just two of us and we sold the dyno off.  Best tuning device ever made.
Lyn Garland

You shouldn't block off the float bowl vents.  You should run a short - about 4" long piece of fuel line up towards the air box.  That vent is to equalize the air pressure between the float bowl and the atmosphere, IIRC, and is necessary for proper fuel flow.  I have done hat on all my 1A1 carbs when I remove the air box and use a Y boot.
Lyn Garlsnd

I use Wossners in our racing RD 250s and like them very much.  Forged pistons require more clearance than cast and should be given some warm up time before being run but they give good performance and life. I would use cast if they were available in the sizes I needed.
Lyn Garland

They are similar but the later models (I don't know when they changed) have a washer integral to the head of the bolt while the earlier ones just have a normal bolt head.
Lyn Garland

But you have to use RD upper triple clamps with the RD fork tubes.  The R5 top of the R5 tubes is gently tapered and pulled into the triple clamp by the top cap while the RD tube is straight and is held in place by a bolt and nut.  I am not sure about the size of the triple clamps; maybe the R5 and RD have the same dimensions, maybe not.  My memory is not that good.  The R5 could be narrower.
Lyn Garland

RD 400 do not suffer from a lot of vibration even when being raced.  Could you have solidly mounted exhaust pipes?
Lyn Garland

That's the correct direction but, if the carb is stock, it is not the correct Needle Jet (Nozzle).  Have the carbs been modified?  That is a primary Needle Jet and the 400s come stock with the bleed style jet.
Lyn Garland

I ran the first AMA Superbike Production Series on a RD 350 (along with Scott Clough and a bunch of other guys).  We had to keep the bikes appearance stock but could upgrade suspension, remove lights, etc.  We could port the engines but had to retain the standard exhaust systems.  I ran Daytona and a almost all the other AMA road races east of the Mississippi in that configuration and it was a lot of fun.  My street bikes since that time have always included at least one, sometimes two RDs, and they always had stock exhaust
systems.  Some were ported, some not.  Almost every one had the cylinder heads reconfigured to change the squish clearance because the OEM heads are terrible.  Your engine would probably benefit from having the ports MATCHED to stock specs and cleaned up a bit but there is no need to have them modified.  It would just make riding around town a pain in the butt.  If nothing else have the heads turned to decrease squish clearance.  If you put a lot of miles on the bike an improved ignition system would be a benefit but we had to run the battery and coil when we raced them and while they took a lot of attention they worked well.
Lyn Garland

I think your short term goals are pretty good but wonder about replacing the cylinder heads.  My experience with the RDs has always been to try to improve cylinder head cooling; fashioning ducts to direct air over the heads, running Daytona Special heads on conventional 400 engines, and even welding on additional fins (early in the game).  You appear to have DG, or some other special, heads on the engine.  Why not have those combustion chambers reshaped to meet your current needs? 

Changing pipes, porting and V Force reeds is a good idea.  I don't like boost bottles but the crossover is helpful in smoothing out the engine.  I have used VM 28s bored to 29.5mm for years and like them very much but many, many guys of the forum are using flat slides now and are happy with them.  I have Lectron's on our Spondon TZ and they are very crisp out of the corners and work well.
Save the 520 chain conversion until you get the 400 transmission but that is worth the effort too.

I think weight reduction and keeping the bike look stock will be kind of difficult.  Replacing wheel rims, the brake disc, etc will do some but to keep it looking stock will probably keep it kind of heavy. 
Lyn Garland 

Maybe sticking my neck out and showing more ignorance than knowledge, but ... in the quest for performance, wouldn't one generally want to raise (instead of lower) the cylinders with thicker base gaskets and deck/skim to regain proper compression /squish?

That was quite a common way to increase power simply, easily, and cheaply years ago and it works really well with stock exhaust systems.  To be rather crude, you don't even have to modify or clean the ports; just raise the cylinder two millimeters with a shim and adjust the top side by milling the top of the cylinder or milling the cylinder and turning a bit off the head to eliminate dead spot at the edge of the combustion chamber where detonation is known to start.  Can be done easily with a Bridgeport and a Logan.  It ain't necessarily pretty, from the inside, but it looks stock and they will run really good for a "stock" bike.  Been there done that.
Lyn Garland