rerb Posted November 22 Posted November 22 Busy winter ahead... extending and bracing a spare swingarm 6 inches over, going efi, and putting better internals in. All to run 200+ mph at a LSR event in July. Unfortunately I don't have Carillo money, and the rods I bought (maxpeeding rods) are only rated for 9k rpms. Not a big issue since power peaks at 8300 or so especially with long gearing. But I've calculated that with a 17/40 sprocket setup (which seems to be the tallest I can reasonably install given parts availability and chain clearance to the swingarm pivot) I need to spin the motor at 9200 to barely reach 200. Sure it'll work for now, but once I do 200 maybe I'll want 225 next. I know hayabusas have some tall ratio gears for sale but haven't seen any for a bandit. I have a spare gearbox sitting around and will get measurements and start looking around, but wanted to know if anyone was aware of a drop in 5th gear set from another suzuki that fits the forks/shaft diameter/spacing Thanks. Quote
peter1127 Posted November 22 Posted November 22 I have 17/40 too on a gsxr with hayabusa swingarm. A bit of a pig from standstill so taller 5th would be interesting for me too! Cant find it either. Regarding the maxspeeding rods, I'm about to install those too. Carillo's indeed crazy expensive. Big money to protect the engine, which is only expensive due to the .......rods. They used to have a cheaper version which were not H beam but seems they dont make those anymore. Dont really understand the rpm rating of the maxpeeding rods. A rating lower than oem makes no sense since everybody installing those rods will go to/over the limit....... Must be a mistake right. I put the rpm limit to 10K but that is more to protect the crank, and turbo engines dont benefit much from overrevving other than topspeed. 1 Quote
Arttu Posted November 22 Posted November 22 I would simply forget about that 9000 rpm spec for the rods. They seem to have that for pretty much all their rods, including GSX-R1000 ones which are routinely revved up to 12000+ without issues... 1 Quote
rerb Posted November 22 Author Posted November 22 Good to know! I just wanted to be as safe as possible to avoid an engine lockup holding max power on the big end of the mile and a half. I did a lot of reading on gear manufacting and design instead of studying and I'm going to ask my campuses manufacturing center if they have the ability to mill 4340. They've worked with me before on engine parts for our SAE car, If so I might try and CAD up a gear and see what the cost would be to machine a billet and harden it. I know they have the tools for it but not sure what they'd charge me. Might be over my head on that, but that's why I have 2 spare motors haha. They're more business focused than indivual, if there's any interest from bandit owners in the concept of a taller 5th set works out I might be able to promote it as a prototype for a commercial product and get the senior engineers to help out with design. On a side note, the MTC pistons are over a grand for the kit. As I'm running hayabusa OEMs right now with a shaved head, I was considering ordering a set of wiseco stock cr forged busa pistons and just running those instead, aiming for 9.5 or so CR. They're half the cost but I haven't been able to find much info on what power level they're rated for. I know oem busa pistons are probably good for very low 300s, so I'm assuming a set of forged should be good for the 350 or so I'm shooting for. Anyone gone this route? Otherwise I'll have to remachine my spare stock jugs for 81mm and I'm looking to save as much money as possible (college student) Quote
Arttu Posted November 22 Posted November 22 I think stock Busa pistons are used for over 500hp. I wouldn't worry about their strength as long as you can keep the tuning right. So replacing them with aftermarket pistons at the same compression sounds like wasted money... Instead I would concentrate getting the deck height and squish gap correct. Using Busa rods could be a good choice for that. 1 Quote
rerb Posted November 22 Author Posted November 22 1 hour ago, Arttu said: I think stock Busa pistons are used for over 500hp. I wouldn't worry about their strength as long as you can keep the tuning right. So replacing them with aftermarket pistons at the same compression sounds like wasted money... Instead I would concentrate getting the deck height and squish gap correct. Using Busa rods could be a good choice for that. Oh, good to know! I'm at 9ish :1 cr right now with a mm shaved off the head. I'll use water to find the exact ratio and then a piece of solder to find squish band (that's how you do it right?) To make sure it's fine. I like higher compression which is why I'm going efi to run e85. As far as bottom end bracing goes ill be using APE hardware. After that and stiffer valve springs I think that's all the weak parts of the motor addressed Quote
Arttu Posted November 22 Posted November 22 Yes, definitely a good idea to first measure what compression ration and squish band you have now. Then you can work out what you need to do. And yes, solder wire or clay is one way to measure the squish gap. Or you can measure piston to deck height and head gasket thickness, should be the same. I would aim somewhere between 1.0-1.5mm, preferably to the smaller end if possible. For E85 10-11:1 compression should be good. 1 Quote
Reinhoud Posted November 23 Posted November 23 9200rpm to do 320km/h is actually pretty low revving... Quote
dupersunc Posted November 23 Posted November 23 My Stock rod motors get regularly run to 10,500 on track. Boost doesn't add any significant stress to the rods, its the g force around tdc (revs and rod to stroke ratio) that nails them. Taller 5th is over thinking it, blus the bigger rev drop from 4th to 5th will hurt your top speed runs. Quote
Gixer1460 Posted November 23 Posted November 23 'Horses for courses' . . . . . 10.5k rpm, 4 or 5 times for a few seconds a lap is not the same as 30 - 40 seconds constant load. The rods may not experience 'significant stress' but the loads DO stress related components, particularly the oil / lubrication system. High output engines often suffer rod failure due to either clearance issues and bearing failure or plain oil delivery / pressure loss, leading to catastrophic destruction. I believe rod 'snappage' can be attributed to excess / over revving - generally never an issue with a turbo power adder, nitrous on the other hand is well easy to over power/rev a rod! Quote
rerb Posted November 25 Author Posted November 25 (edited) On 11/23/2024 at 6:36 AM, Gixer1460 said: 'Horses for courses' . . . . . 10.5k rpm, 4 or 5 times for a few seconds a lap is not the same as 30 - 40 seconds constant load. The rods may not experience 'significant stress' but the loads DO stress related components, particularly the oil / lubrication system. High output engines often suffer rod failure due to either clearance issues and bearing failure or plain oil delivery / pressure loss, leading to catastrophic destruction. I believe rod 'snappage' can be attributed to excess / over revving - generally never an issue with a turbo power adder, nitrous on the other hand is well easy to over power/rev a rod! Right, for that reason, I'm having my crank polished and balanced and new main shells put in. I plan to have an oil pressure sensor wired in to set the map to be heavily retarded if pressure or temp crosses a threshold along with a red warning light so I know to clutch in and kill the motor. Also gonna be running 300V. But it seems from what you guys have been saying my concern about RPMs on the maxpeeding rods isn't really necessary. I've heard that they come with fake ARP bolts so a known genuine set of 2000s have been ordered. I still want to explore making a taller 5th as I've talked with the CNC guy at the manufacturing center and someone at a surface coating company who think they're able to help me and that the project is possible. Main reason is if I can run 16/44 or so and still break over 200 easily vs 17/40, which sacrifices 60-130 times or 1/4 ETs. Shifting at 10k will put me just above 8k going into 5th with these ratios which seems fine for a turbo bike, peak power is around 8500 on every dyno I've done so far. I'm thinking 0.833 ratio (20t/24t) as stock 5th is 21t/23t for 0.91. The real challenge is just ensuring proper tooth and dog hardness and case depth with nitride case hardening on 4340 steel without any distortion. Current numbers are 9 thou" depth of 60 C hardness and 39 C core hardness with a tooth surface roughness of 0.4-1.0 µm avg. Ra. I'll throw the cad model in the thread when I'm finished with it, just designing the involute profile now. This is very applicable to my design classes so maybe the professor will even count it as credit for a final project... Thanks for all the advice, I remember my first post here saying I only wanted 180hp or so, someone told me that wouldn't last very long... they were right Edited November 25 by rerb 4 Quote
rerb Posted December 1 Author Posted December 1 (edited) First prototype, going from 21 T to 20 T on the driven gear forces the dogs to be moved down. To account for this (the edges of the dogs do not follow a diameter line of the whole gear, but seem to have their own very small angle) I'll bring the gears that mesh to the 5th gears and the lower half of the case to get 3D scanned. This will help me determine the exact shaft to shaft center distance, dog undercut angle, and the proper angle for the dogs to mesh with the cutouts on the gear next to it. Currently printing these right now on my 3D printer to test fit in the meantime. The factory gears are "non-standard" sized so I'll give the machine shop on campus a visit with the stock gears this week and ask them if it's going to be difficult to cut with what they have. Edited December 1 by rerb 3 Quote
Gixer1460 Posted December 1 Posted December 1 Forgive me here as I know jack about gear cutting but you seem to be planning on cutting a single gear - 1 tooth less than stock? I always thought gears (for any ratio) were made as pairs due to relative geometries ie both are on shafts with fixed separation so changing tooth count on one messes with tooth engagement ? Quote
Duckndive Posted December 1 Posted December 1 54 minutes ago, Gixer1460 said: Forgive me here as I know jack about gear cutting but you seem to be planning on cutting a single gear - 1 tooth less than stock? I always thought gears (for any ratio) were made as pairs due to relative geometries ie both are on shafts with fixed separation so changing tooth count on one messes with tooth engagement ? Yes its a dark art But Cannon "RIP" Engineering made a taller gear for them busa things that only involved replacing a single gear ... Quote
Arttu Posted December 1 Posted December 1 I think if you go by the book the gears definitely must be designed as pairs. But apparently in real life you can bend that rule somehow. There are some aftermarket gearbox gears that allow changing the ratio by replacing only single gear. Also similar high speed oil pump gears are quite common. I guess strength and longevity aren't as good as with a matching pair. 2 Quote
rerb Posted December 1 Author Posted December 1 (edited) 8 hours ago, Gixer1460 said: Forgive me here as I know jack about gear cutting but you seem to be planning on cutting a single gear - 1 tooth less than stock? I always thought gears (for any ratio) were made as pairs due to relative geometries ie both are on shafts with fixed separation so changing tooth count on one messes with tooth engagement ? I'm planning on making a new 5th driving and 5th driven. The stock is 21 teeth driven 23 teeth driving, i want to go for a 20t driven and 24t driving. The difference will be in diameter, but these will actually have the same "module" (or size) as the stock gears since the total teeth count is still 44 with the same center to center distance. The new ones will just have slightly different diameters, one larger one smaller. However, the stock 21 tooth gear has the dogs right at the base of the gear teeth. Since the new one is smaller, that forces the dogs further down. If that causes issues with where it meshes, I might have to do a 21t/24 or 25t in which case I'll have to pay more attention to how the other products mentioned are able to replace just a single gear. I'm focusing solely on strength here, so I'd rather make a pair instead of just one. if the gears eat themselves and start whining after a few seasons from poor clearances or improper contact area then oh well. Far better than them blowing themselves up on a top speed run The 3d print turned out alright, warping around the teeth but this printer has always given me problems. Edited December 1 by rerb Quote
eddiegsx Posted December 1 Posted December 1 38 minutes ago, rerb said: I'm planning on making a new 5th driving and 5th driven. The stock is 21 teeth driven 23 teeth driving, i want to go for a 20t driven and 24t driving. The difference will be in diameter, but these will actually have the same "module" (or size) as the stock gears since the total teeth count is still 44 with the same center to center distance. The new ones will just have slightly different diameters, one larger one smaller. However, the stock 21 tooth gear has the dogs right at the base of the gear teeth. Since the new one is smaller, that forces the dogs further down. If that causes issues with where it meshes, I might have to do a 21t/24 or 25t in which case I'll have to pay more attention to how the other products mentioned are able to replace just a single gear. I'm focusing solely on strength here, so I'd rather make a pair instead of just one. if the gears eat themselves and start whining after a few seasons from poor clearances or improper contact area then oh well. Far better than them blowing themselves up on a top speed run The 3d print turned out alright, warping around the teeth but this printer has always given me problems. Jeez,even reading all this makes my head hurt. Clever stuff and way beyond my pay scale. Quote
Gixer1460 Posted December 1 Posted December 1 All good - making a pair of matching gears wasn't clear! Quote
dupersunc Posted December 1 Posted December 1 19 hours ago, rerb said: First prototype, going from 21 T to 20 T on the driven gear forces the dogs to be moved down. To account for this (the edges of the dogs do not follow a diameter line of the whole gear, but seem to have their own very small angle) I'll bring the gears that mesh to the 5th gears and the lower half of the case to get 3D scanned. This will help me determine the exact shaft to shaft center distance, dog undercut angle, and the proper angle for the dogs to mesh with the cutouts on the gear next to it. Currently printing these right now on my 3D printer to test fit in the meantime. The factory gears are "non-standard" sized so I'll give the machine shop on campus a visit with the stock gears this week and ask them if it's going to be difficult to cut with what they have. Get the ratios they want, on the same shaft centres, it's usual for manufacturers to use modified modules to get the teeth count required. 1 Quote
peter1127 Posted December 2 Posted December 2 (edited) If its just a machine shop, they probably gonna recommend EDM/wirecut directly in hardened steel. Couple of problems with that: if it is trough hardened steel the gear is too brittle and EDM surface finish is not ideal either regarding wear and fatigue strength. You need hobbing, heat threatment and grinding. I'm by no means a gear expert, but enough to know that high performance gear manufacturing is a specialist job with zero chance of success if you dont know what you are doing. I dont think I need to paint a picture of a shattered gear set in your freshly build motor at 200+ mph..... I recommend to let a proper gear manufacturer do this, or not to do it at all. Edited December 2 by peter1127 Quote
rerb Posted December 2 Author Posted December 2 5 hours ago, peter1127 said: If its just a machine shop, they probably gonna recommend EDM/wirecut directly in hardened steel. Couple of problems with that: if it is trough hardened steel the gear is too brittle and EDM surface finish is not ideal either regarding wear and fatigue strength. You need hobbing, heat threatment and grinding. I'm by no means a gear expert, but enough to know that high performance gear manufacturing is a specialist job with zero chance of success if you dont know what you are doing. I dont think I need to paint a picture of a shattered gear set in your freshly build motor at 200+ mph..... I recommend to let a proper gear manufacturer do this, or not to do it at all. True, I know little on the actual machining side of things. I say it's a "machine shop" but it's more of a high end manufacturing center. The guy I talked to operates a huge 6 axis lathe and thinks the profile can be machined to fairly good accuracy. From there I'll still have to talk more with the surface coating place about exact hardening specs but I know they're willing to take the job on. Like you said will probably need to be ground after hardening which I haven't looked into too much. This is definitely a bit of a long shot, but I'll keep working at it until I hit a wall.. nows the time to try before I lose access to these resources after graduation. if by some chance I do end up with a final product and don't trust it to go into the built motor I'll test it out in my spare bandit I have taken apart right now Quote
1100n Posted December 6 Posted December 6 cool project very interested in how you progress with the gear set Quote
rerb Posted December 13 Author Posted December 13 Small update, current driven gear design wont work, the dogs wont slip into the gear next to it because of the smaller radius. Currently deciding on what path to take from there, either lift the dogs past the tooth profile (strength concerns), modify the module / tooth count to make it fit, or expand the dog channel on the other gear a little for the dogs to mesh properly. Force analysis is good for the gears for 300 ft/lb of torque (over estimate) from the motor, so the current design is definitely strong enough. I have gotten a good idea on price if I had the machine shop do it for me, unfortunately it's too involved to be a side project, would need to be treated as a normal job for them. Around $1-2k for the labor of making both gears, $2-300 for heat treat and $200 or so for materials. However, if I do it myself, I won't have to pay any labor. In order to do it myself, I need to be employed there and trained on the machines to a well enough degree of competency. On the bright side, I have an interview there today for a student position which grants me access to all the machines outside of business hours. I'm not calling it quits on this, but It'll probably be a while before I'd be capable of programming the 6 axis well enough to make a part like this (assuming I get hired.) Until then, I don't want to make nothing so I might try something easier like windowed engine covers that'll fit a lockup. I'll update with any progress after finals are over. 1 Quote
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