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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.

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

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.

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.

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

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

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)

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.

Great info, I used Garrett's equations to calculate my numbers on pump gas, probably not super accurate. Might skip the porting and just get the valve job done, I already know the guides, seals and valve seats are a bit worn from oil burning and "eh" leakdown test results. I agree, I want 400 for going to 1/4 ,1/8, and 1.5 mile events where I plan to swap out the rear for a longer swingarm and grippier tire, and run e85. Pump gas tune will probably be 310-340. I'll have to figure out compression ratio for a setup with low 300's on pump and ~400 on E, i did shave the deck of the cyls down a mm on 20 psi with just busa pistons and the bump in low/mid end power is something I don't want to miss too much of by going with a real low CR. I hit 260hp+ boost creeping on 26 psi, but 10:1 AFR and 20 deg of timing pulled out which i believe is a pretty conservative tune. MTC says 10:1 with their turbo pistons and I think im around 9.8-10:1 now, so it shouldn't be too bad. I was under the impression BB turbos would cook themselves pretty fast without coolant, but if not that's definitely the better option

True, real number on the daily tune will probably be around 350. I do have watermeth and low ambient temps where I am, but knock could become an issue. On race days, I will have it on e85 which is a pain the ass to get here, but possible for events. That should be enough to run 400 without cooking anything (I hope). Looking at the compressor map for the gt30/71 if I can get enough efficiency with a ported head, that should be a pretty damn perfect turbo what I'm looking for. Wow, im making 250 at around 21 psi so that's good to see the effect a ported head can have. At that rate I should be able to run low 30s and still make power, thanks for that info

Hi, im building a better motor for my boosted b12, and am currently sizing turbos for my power goals (~400). I'm going mtc turbo pistons and maxpeeding rods with all the APE head/crankcase hardware with an efi conversion. According to my calculations I'll need about 38 psi of boost to achieve this with a pressure ratio of ~3.5, and mass flow rate of about 33 pounds of air/min. These are very fucky numbers and after a few hours of searching I couldn't find a turbo where the compressor map doesn't plot my setup at, or beyond the surge line. I can't run e85 too often or methanol because it's not available here (trying to keep it a streetbike) so I can't do much with fueling to adjust those numbers. But I've been told a ported head will make the same power with less boost, I'm going to send mine off to APE for an oversized valve job and port, but I still want to know how much it'll help so i can order the right turbo as soon as I can and swap the flange on the manifold. So guys with ported heads, what boost and horsepower are you at?? Thanks!

I'm running 4 clutch springs in my bandit, up from the regular 2 and it's been working great. All i did was shave down the nut the same amount of thickness as the 2 springs. However I've noticed that the clutch slave has deformed the metal guard over it enough to break it loose, rubbing it against the chain. When checked against my parts bike the first pushrod under the sprocket cover slides into the motor 8mm more than the stock motor, causing the slave to extend further than the guard allows, pushing it into the chain. 2 extra springs shouldn't add that much distance from what I remember seeing when I was working in the clutch area. I did replace the middle pushrod with one from a 2001 but they share the same part number to my 99 so it's not that. I'm just going to get some 5mm diameter rod and cut my own to lengthen it, but was curious if anyone else ran into this. I'm too poor for a lockup.

(99 b12) I'm reworking a lot of the sloppier parts of my bike from when I first built it 3 years ago, one of which is the fuel system. I have a standard size 255 lph fuel pump that was kind of "hanging" by the braided line between the battery and plenum, and have decided to build a sheet metal mounting plate for both. However I'm running into the problem where with the fittings installed the pump and filter are simply too long to fit horizontally in the area! I looked online for shorter pumps, however it seems Google has gotten far worse at filtering listings. I'd like to see what setups other folks here are running for mounting their pumps? I also remember seeing some in-tank methods used, but can't find the thread that it was in. Not sure if that's worth the headache of cutting open the tank or not thought!

Install error (i think?)- not sure how but last szn after taking off the head, i noticed 3 of the middle nuts were stripped off the studs. They were torqued to 50 ft lbs (and triple checked) when I put it together. They 100% were not stripped when I put it together (I even have an old video of checking torque right before throwing the valve cover on) I think I had the wrong length studs installed? I got a new set and made sure that they were in the correct orientation. rechecked torque at 55 ft lbs after letting it sit for a night. There were some scratches on the top of the jugs under the HG where the nuts were stripped, I assumed those were from the hg. I think I might have used those copper washers which I heard can lose tension overtime, who makes a good alternative? Main reason for the meth is i was about 200 deg intake temps on boost which was a little hot for my liking. With meth I sit around 160

Wow, glad to know. Whats limiting me is probably the afr which is fairly rich, but my power tapers off far sooner than the other charts of stock cams show. Next season I'll spice up the tune a little and maybe turn down the meth and see what that nets me. I had some issues with the APE head nuts coming loosing causing the head gasket to shimmy around a little, I'll probably pop the head off and inspect too. I have busa pistons but also shaved the cylinder a mm for extra compression so it's still fairly high.