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Stray

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Everything posted by Stray

  1. Was at Donington Park on a cruiser getting embarrassed by the superbikes. My favourite bike there was a gorgeous VFR750 belonging to track instructor John Chambers who’s won multiple awards in the vintage motorcycle races on it. Aside from good looking this thing is FAST and he was instructing some upcoming BSB riders on it. Of course John is very talented but he was teaching some of the fastest riders in the country how to go faster on a VFR and it really tickled me! Check out his socials if you’re into that sort of thing and you’ll read all about the bike there. My welder friend will be machining some rearset adapters for the VFR750. Also came across some other lovely classic bikes being raced pretty hard - these guys are running in the intermediate group and were overtaking modern machines! These two were raced by a very attractive young lady who’s less than 5 feet tall and seriously capable. Nice to see old bikes being used as they were intended and not turned into dead museum pieces.
  2. Messing about with radiator sizes today but nothing is perfect. Got my hands on some grubby ones today off a “92 VFR750 and CBR600 F3, to compare with the F4i unit in a previous post. Here you can see the size difference between them (from top): 1. VFR 800 5th gen rads 2. VFR 750 1992 rad 3. CBR F4i curved rad 4. CBR F3 curved rad The CBR and VFR750 units are the same width, but the curved roads have an extra 2cm surface area. CBR F3 and F4i rads stacked. The F4i has 3 more rows in height. VFR750 rad stacked on top shows it’s 3 rows shorter than the F3, and 6 rows shorter than the F4i. Curved F3 rad tried on for size. Width is fine but the very bottom might make contact if forks are fully compressed. I could easily remove the lower row but would prefer a cleaner solution. Hose coupling on left is turned downwards, whereas I’d prefer it facing backwards. Advantage of the curve is there’s more room for a possible fan on the left (as you sit on the bike) because the cylinder head isn’t central and there’s a bit more room there. But would have to be a very small fan! Mounted slightly off centre as mounting eyelets get in the way. These will be ground off. VFR750 ‘92 rad tried on for size. Significantly better clearance here with no danger of wheel contact at full compression. Advantage is filler neck and hose barbs are all in the right place and orientation. Disadvantage is almost no room for a fan and reduced cooling capacity (compared to F3 and F4i). Easiest route is the 750 but I’d like the increased cooling from the CBRs. Also, I’d like to mount a fan if possible for traffic. Might have to go with a custom rad after all… And here’s a pic of the two 5th gens side-by-side. The race bike (behind) feels light as a toy compared to the stock one (in front). Even pulling them up off the side stand it’s obvious which is lighter.
  3. At 8,000rpm it’ll suck in pigeons At 10,000rpm it will suck in clouds At 12,000rpm it’ll suck me in, roll to a stop and tip over on its side…
  4. Looks wise, what do you think of this? Bikini fairing plus bug spoiler - no full fairing.
  5. Another small step forward with the airbox. More of a stop-gap until ram air is sorted: an open lid box! Mohawk was gracious enough to send me one of his open airbox lids to fit on the race bike. And I butchered it even more! I’ve basically just cut everything off except the rim that holds the filter. If she can’t breathe through this then she’s really not trying… Used a Dremel cutting wheel to start, shaped with die grinder and hand files, and then ran a heat gun over the sharp bits to smooth them out somewhat. It’s rougher than a badger’s bum but does the job and nobody will see it. Pictures mounted on another 5th gen as the race bike doesn’t have throttle bodies on yet (watch this space for 6th gen throttle bodies). Incidentally, that Pipercross air filter was a real pain to fit. Was about 4mm too long and kept popping out of the grooves. Had to tighten one screw at a time whilst poking a flat screwdriver down the side as I went along. Took over 30 minutes to force that air filter in and I may still have pinched some of the rubber in a few places. Let’s hope the filter media is better. Open air boxes were popular with the RC30 so let’s see.
  6. Thanks Phantom for reminding me about the Ozzie boys who tried ram air on their 4th gen - remember reading about it a couple years ago. The 5th gen has injection: does that matter? I’m looking at the F4i setup and there doesn’t seem to be any trickery on it to help equalise pressures. Just the long snorkels and a water/sound trap. Was going to transfer all that wholesale. Also thanks Bren for your custom rad suggestion. Trouble is nobody makes anything in the UK any more, and if they do, it’s brutally expensive. Any suggestions about where I should look? Or should I just take a hacksaw to the CBR 600 rad?
  7. Bit more minor progress: trying a CBR 600 front rad on for size with standard 5th gen catless headers. The CBR rad is bigger than the 4th gen units I’ve been eyeballing, and it’s curved to catch more air. Problem is it also hangs down a bit more than 4th gen VFR models and will likely interfere with the ZX6R USD forks at full compression. Forks have about 10cm of travel so I used a chopstick to measure where the wheel/fender might go when forks bottom out. Thinking I’ll have to cut off the bottom 4 rows of the CBR rad and solder it back up. Solder rather than TIG as I’m worried welding will melt the flux bonding the core to the tanks. Unless you guys have a better suggestion? I’ve repaired oil coolers and rads with that “magic” alumiweld stuff. Maybe that’s the way to go. Will also need to solder/weld some new mounting brackets. The inlet and outlet are in the right locations but those 90* spigots will have to come off and be replaced with straight hose unions. Bottom left outlet is just above the lower rows I plan to cut off - lucky. View from above and through the frame (airbox and throttle bodies removed). Gives an idea on where I’ll mount it - where the original oil cooler bracket used to bolt up. Haven’t figured out where to mount the bottom. Was thinking to use the valve cover bolts but worried about that tearing up the rad. If it’s fixed to frame at the top and to the engine at the bottom, there will likely be some play, no? Doesn’t the engine vibrate/move independently of the frame? So as the top (frame) mounts stay still, the bottom (engine) mounts will vibrate violently and tear up the rad. Or am I wrong? Has anyone seen a radiator mounted to both the frame and engine at the same time? Is it safe to do? Am I overthinking it?
  8. Stumbled over this on the interwebs: https://motoridersuniverse.com/b1311521 Really sexy looking 5th gen cafe racer. Fantastic bodywork but it’s all 3D printed one-off. Shame really as it really suits the bike. The builder is a great artist but poor mechanic. He could have taken the opportunity to improve the bike quite a lot but opted to just throw on the printed fairings.
  9. I honestly don’t think this’ll work but was messing about with possibly installing ram air from a CBR600F4i. Picked up the air box and tubes on a whim - worth a try, no? F4i tubes go over the frame and under the tank, which is notched to allow tubes to fit. No such luxuries on the VFR, although I could “modify” the tank seam with a hammer to make a bit more room.. Even after such a modification, the tank would need to shimmed up a bit at the front. Put the bottom of the F4i air box in the VFR for trial fit and it’s taller than the original unit. Would need to be raised still further at the front to have tubes facing forward. Just to clarify, the air tubes are right-way-up but the F4i airbox is up-side-down in these pics. F4i draws air in from the bottom of the airbox and VFR draws air from the top. Question: does anyone know what the hollow “fins” on the air tubes do? My guess is the lower one collects water from wet intake air. The top one is just a hollow triangle with a little hole into the air tube. Does it regulate pressure or something? Air tubes too low and pointing downwards. VFR air box cover vs bottom of F4i airbox. Toying with the idea of grafting the bottom part of the F4i onto the roof of the VFR so I can run ram air tubes. Angles are all wrong though. Interesting how the F4i breathing holes are bigger than the VFR’s. The snorkel and flapper openings are about 30% smaller than the F4i air tubes. Bigger engine has smaller nostrils. Most obvious in the 3rd pic below. F4i velocity stacks (staggered heights) are also around 1.5mm wider than VFR at the bottom, and about 2.5mm at the top. Again, the bigger engine has smaller nostrils. VFR air filter is slightly bigger, though.
  10. Another step forward in the VFR racer saga: Ducati rear brake installed with hose running through swingarm. Big thanks to the guys on the site who pioneered this setup. Whilst slightly different, mine owes y’all a massive debt. Parts used: - Ducati 848 caliper & master cylinder - Ducati 916 brake rod and clevis - Custom 7mm stainless pin and R clip - 2 x Ducati 848 caliper hanger brackets welded together - custom brake hose with heat/chafe shield to protect from exhaust heat and swingarm rub (105cm long with 90 and 20 degree banjos) - rubber grommet for swingarm hole to minimise rubbing Here’s the brake caliper hanger made up from 2 x Ducati 848 brackets welded together. Needed to lengthen the adjustment hole to match the VFR swingarm torque arm pin boss. It’s a couple inches closer on the Duc. Matching the two parts for tig was a b1tch. Duc SSSA is surprisingly similar to the VFR unit. The VFR brake pedal pivot uses an odd 7mm swivel pin. The VFR foot peg bracket and pedal have a 7mm hole. The Duc uses 6mm. So I had to make a 7mm pin (couldn’t find one to buy) out of a M8 stainless bolt. Needs to be a long bolt with an unthreaded section as the threaded bit only has about 6.5mm of “meat” on it. Chucked the bolt into a drill and pressed a file against it as it spun to reduce the diameter from 8-7mm. Times like these I’d love to have a lathe… Then drilled a 1.5mm hole for the R clip. Used a hand drill with tungsten carbide bit: love these drill bits! Tickled the bolt head with an angle grinder to finish. Drilled out the Ducati clevis to 7mm and we’re in business! Lots of hand filing and finishing later it was done. The Ducati master cylinder isn’t quite aligned with the brake pedal so had to file the lever down a bit to match. The Brembo brake master also has smaller mounting hole spacing than the VFR’s Nissin unit. Had to bring the VFR hanger holes “closer” by 5mm. Used a Dremel and rat tail file to cut the holes closer to each other and mounted the master cylinder with 5mm bolts (6mm heads would no longer fit in the holes). Here it is fully installed. You can see the custom brake line with 90 degree banjo at the top. Feeds into the swingarm hole on the right, near the right foot peg. Took HOURS to thread a wire through the swingarm and out that hole. Lots of swearing. And when I finally pulled the brake hose through, discovered it was way too long so had to buy another one and do it all again. Horrible job. Existing drain hole under the swingarm had to be expanded (used a carbide burr in a Dremel) to let the banjo pass through. Heat shield on both ends protects against chafing, along with rubber grommet in the drain hole. Bottom banjo has a 20 degree bend. Next time I might go with 45 degrees. Left a bit of line inside the swingarm to account for pull at full rear shock expansion, like when going over the Mountain at Cadwell Park! For anyone interested, line is 105cm long, with 90 banjo on one end and 20 degree on the other. Here with wheel mounted and everything in place.
  11. Hi Stray, Thank you for your donation of 25.00 USD. We look forward to improving the forums with your donation. Thanks VFRDiscussion
  12. Bit more progress, albeit minor. Got to measuring and designing the subframe. For the record, the stock subframe sits under the NSR250 fairing. I’m using this as a guide/template to measure the new one before fabricating parts. Was thinking about extending the seat to follow the tank crease at the knee - what do you think? Also thinking of following that seat line with the fairing so it’s one clean line, parallel with the frame. This part of the 5th gen always seemed untidy to me, like they had a plan but changed it. Again, what do you think? I’ve even been thinking of covering that lower triangle on the tank (under the green pen) in the same material as the seat for continuity. Here’s what the seat pan looks like in situ. Need to think about how I want to deal with the hole where the rider’s butt goes. Might just seal it with plastic plate. Also got me thinking more about why the NSR cowl/cover has all these holes. Turns out the two on the side (where the blue end of the pen sits) are for a passenger seat pan that slots in. Will have to weld those shut. But what about the NACA duct on top (where the pointy end of the pen is)? What purpose could that possibly serve other than to let rain into the battery box? It’s absurd! I was working late at night and couldn’t break out the angle grinder so cut the ends of the stock subframe off by hand with a hacksaw. No joke, it took over 30 minutes (with cutting oil!) and I was sweating like a galley slave at the end! Finally, if anyone wants to do this mod the stock subframe will fit if you cut the rear corners off like I did. You don’t have to even cut the Frankenstein bolt (I did but you don’t have to). Only a very small part of the stock subframe shows (where the yellow pen is pointing) if you kneel down low. You’d have to weld on tabs for the fairing and lights but that’s easy on steel. Interestingly, the NSR fairing mounts are a hot mess. If you look at a stock NSR MC21 subframe you’ll see what I mean. I’ll have to recreate that hot mess of welded tabs to make this work...wish me luck!
  13. Thanks mate. Can’t wait to see the finished product either but my God she’s taking her time! Just saw pictures of your RS850 - got to be one of the most beautiful motorcycles I’ve ever seen! Unfortunately I’m now committed to the MC21 seat and am measuring up subframe parts. But I’d still love to see your bike in the flesh. I’ll be racing in Mallory Park on the 8th if you fancy coming for a jaunt. The Triumph, Norton and EMRA boys will be there - should be a hoot! Free to watch if you come early enough before the racing starts. It’s an odd circuit and you can only access it by riding the wrong way round the track. So once the racing starts there’s no way in until the next break.
  14. I love the lean angle you can achieve on that RC45, BLS!
  15. Another minor bit of progress - initial trial fit of NSR 250 MC21 tail fairing (Chinese plastics) and cut down 5th gen seat. Still needs a great deal of sculpting for both seat and fairing, but it’s a cautious start. Now just need to settle on the rear fairing angle and build a subframe. Which one do you prefer? Slightly upward pointing tail: Or slightly lower pointing tail: The MC21 is a much smaller/narrower machine than a 5th gen and the tank is narrower too. The MC21 fairing sculpts inwards at the front and fouls against the 5th gen frame, making it impossible to line things up properly. So I cut the offending pieces off and straightened them with a heat gun, some old angle iron and a clamp. You can see where I cut them off in the previous picture; there’s a gaping hole just where the fairing meets the main frame. Below you can see the grey plastic piece sandwiched between two black angle iron pieces and a blue Irwin clamp. By the way, these Irwin clamps are amongst the most useful tools I’ve ever bought! Came out straight enough with minor ripples that will sand out. Can’t tell it was ever “sculpted” in the photo. The idea is to glue them back on (solvent welding) but if I was doing this again I’d just have bent them on the fairing without cutting them out. Now can somebody please tell me why the MC21 has a NACA duct on the rear fairing cover? What purpose does that serve other than to let rain water in? And one more thing: why does the 5th gen have a sculpted crease on the tank (where the seat meets the tank) and no fairing to go there? It seems like they initially planned to extend the rear fairing and cover that hole where the rear cylinder is visible but then changed their minds. Maybe to let hot air out and stop the rear cylinders overheating?
  16. I bet there was an air bubble trapped in that run. Air bubbles can cause poor cooling. Otherwise distilled water is a better coolant than “coolant”. The only reason we mix water with other stuff is to stop internal corrosion.
  17. Minor bit of progress, but an important step made this weekend: got rear brake bracket welded for 848 wheel/caliper conversion. The 848 brake torque arm is a cast & forged aluminium piece fixed with a 12mm lug in the swingarm. The 5th gen equivalent uses a bracket and a dogbone fixed with a 10mm bolt that’s about 47mm too far for the 848 bracket to reach (depending on how the eccentric is situated). I tried making various brackets and bolts but there isn’t enough clearance. So I extended the 848 bracket with a piece from another 848 bracket. Traced it on paper and drew out the design crudely in pencil. Then cut out the piece to add as a stencil and traced it on the donor part. After that, a tiresome couple hours of cutting, grinding, filing and shaping to make it match the profile of the other part for welding. It’s a thin piece of aluminium with lots of complex angles so had to make sure the welding gap was minimal. Then bevel the edges and get welding. Came out quite nice in the end with minimal distortion. Hope you like my plait welds! Not the prettiest job but it’ll hold. Maybe some paint to smarten it up... Few notes: the internet is so full of sh1t and misinformation it gets me every time. Every source I’ve read (including dedicated welding sites) say cast aluminium wants 4043 filler rod because of its ductility to avoid stress cracking as it cools. They also say 5356 is unsuitable for cast because it’s prone to cracking and difficult to work with. They also say to never mix the two rod types: if you apply one and then decide to apply another the first should be completely ground off first. Well, that’s all horse sh1t. I started with 4043 and it cracked before my eyes. So I tried the 5356 over the cracks and that went on a dream. So I went over the whole thing again with 5356 (no grinding) and used the side-to-side method to cover more area and deposit more rod volume. That’s why it looks like a plait. In short, it was EXACTLY THE OPPOSITE of what the welding forums were saying. So don’t believe what you read on the internet. Don’t even believe me! Get proper professional opinions and make up your own mind.
  18. Sorry Mike, I haven’t got that far yet. Still battling with subframes and bodywork. The injection system will be the last bit to get done. Still have electrics, new coolant system, suspension upgrades...and so on. Mightbe a while before I post an update but certainly will when the time comes.
  19. Jim, have you put spark leads on correct plugs? Many of us have got that wrong and engine won’t fire.
  20. Pics of the SP1 race tail as promised. Got the rear wheel and front fairings off so it’s hard to picture. Will need some trimming at the tank. Not really the period look but not bad. Any good? Compared to the previous ones?
  21. Thanks bmart! Do you mean the half-naked without the lower fairings? The one with a chin spoiler? Love the FJ, by the way. One of the greatest bikes ever made. Really solid air cooled engines!
  22. Thanks for your input, Dangeruss! It’s good to know you’re in this rabbit hole with me. Can’t wait to see yours with the SP2 tail. Please post ASAP!
  23. So folks, have I gone crazy? Do you like any of the below or am I barking mad? You’ve got to try imagine it properly fitted and painted, which I’ll agree is difficult. For any new visitors, this is 5th gen that I’m building into a retro road racer. It’s remit will be fast road use, touring and track days. Going for the 80’s endurance racer vibe. VF400 front cowl with VFR400 tail (NC24 or something?) Standard VFR800 seat with VFR400 rear cowl just for silhouette. Suzuki GS550 tail (I liked the ducktail little wings!) CBR600 2016 seat (not sure it works with the classic styling of the other bits but it’s SO light!) A cafe racer hump I had on the shelf just for giggles and ideas. Maybe a bigger one would work but I think it needs to be a boxy tail from the 80’s instead of a hump from the 60’s... Now the VFR800 standard seat on its own. Imagine a tail fairing that made up the pillion seat section and ended where the seat does. That’s a good 5 inches shorter than the original fairing and quite slim. I think it looks good (ignore the 5th gen side fairing for now). Trying out a half-naked look with headlight fairing and chin spoiler (I think it’s off a half-naked VF400). No side fairings. Got an SP1 race tail to try tomorrow but it’s HUGE and might spoil the look. Will post pic ASAP. I’m desperate to try an NSR250 (MC21) and NC35 (VFR400) Seat but can’t keep buying fairings as money’s tight and I’ve got a whole bunch already. Also, a VF1000 or VF750 seat might be nice to try. If anyone in the Midlands (England) has any I could borrow that would really help. Let me know what you think! Stray
  24. Quick update: - 929 injectors are a drop in (thanks Mohawk) - 954 injectors fit in 929 throttle bodies but wiring is all wrong Verdict = 929 injectors for the win!
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