Dog Gear Boxes Explained & A Little Cooper S

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[@cmiimages]

One of the greatest driving skills with manual gearboxes is understanding how to double de clutch... which is very different from blipping the throttle between gear changes. I've been driving my classic now for a year with out synchro on 3rd-4th gear, but it is not a problem when you know how to double de clutch, yes, I hope to pull engine and gearbox soon to correct the problem, but its amazing how enjoyable the DD clutch art is. So how did I learn, my father taught me how to drive an old Bedford truck (Way back in the sixties) with a four speed crash box... once you learn you never forget.

[@franciscomelendez3894]

Great explanation Paul!

[@HREIRL]

Thanks Fran 👍

[@tonycamplin8607]

Another really great video with everything simply explained, really useful for those not in the know. You modern mini experts are very lucky to have such a lot of choice of components to use, back in the early 1960s ofcourse we didn't have those newer components. BMC did however offer quite a range gear options etc though their Special Tuning Department and also supplied a LSD kit. As a footnote I still heal and toe driving modern cars, I think that even with a modern gearbox it makes for smoother driving and on my 1937 Austin Seven ofcourse always double declutch. I learnt to drive on non syncromesh gearboxes so it all became automatic. Looking forward to the whole series.

[@HREIRL]

Thanks Tony I could do with you on hand to show some of my customers that technique alot of gearboxes would last a loot longer 😂

[@ChrisEdmunds-kv2jr]

Brilliant . Thank You .

[@cw2126]

Great watch 👍👍👍

[@HREIRL]

Thanks CW

[@mikeakhurst1855]

Looking forward to you building the cooper s gearbox

[@iainmacknish5220]

22G1128 is a great gearbox case. Gives a lovely fast precise gear change when you can eliminate all the free play in the linkage. I also run the KAD pinion support housing mine after breaking teeth off the crown wheel and pinion. Always thought that there must be on/off throttle 'slack' in a dog box, your the first person I've heard mention it.

[@HREIRL]

Yes Iain, they are a great box and will work super for this application. Yes as a road box they definitely have a lot of slop

[@paullorman8924]

Just built a 1128 close ratio box for my S. Looking forward to seeing you do it! Please show how to get the idler gear bearings out of the flywheel housing.

[@HREIRL]

Will do Paul 👍

[@garydempsey6124]

Savage stuff lads well done ❤️

[@HREIRL]

Thanks Gaz

[@aussiebloke609]

Never drove with dog gears before, but I'm guessing there's a lot of driveline shunting at low speeds and in low gears with a dog box. Good news that the wider gears in the box can handle the added impact on the teeth, but one hopes the CVs and axles are equally beefy. Edit: And you covered this yourself. I really need to watch the whole video before I start typing. LOL Cheers, Paul! :-)

[@HREIRL]

Yup lots of slop but that’s what makes them work 👍

[@chriswright3062]

Had 2 Cooper S's in the past both with full race engines on the road and yes was a little while back now. The first one in the UK had 95 bhp at the wheels running a normal S box but with a straight cut transfer gear set, never had a transmission with this car. Move to AUS and built another S with about 120 bhp at the crank I think, could never get the normal transfer gear to last with the power, box was straight cut and never a problem. So I'd like to see your thoughts on a drop set gear set Paul?

[@HREIRL]

Hi Chris very intresting thanks for taking the time to share that with us. There is a few options when dealing with the drop gears but as you have experienced when the the power and RPM gets high straight cut transfer’s really help reduce the side loading on the drop gear train the main weakness of the transfer gears is the idle gear in the middle and the ability of the trust washer to take up the trust force at high rpm

[@arrindaley3714]

I thought there were gains in efficiency with straight cut gears so less power losses through the gearbox, the other reason I've heard is the dog engagement is quicker allowing quicker gear shifts, am I correct?

[@HREIRL]

Arrin, you are most correct there is a marginal reduction in losses from straight cut gears over helical as it has less side load. secondly you are correct faster shifting in the right hands can be achieved with dog engagement 👍

[@allanscott2778]

Very interesting video on the different types of gears Paul, question is what in your opinion are the best dog gear kits available and are they a straight forward fitment within the gear casing.

[@HREIRL]

Hi Allan, there is some very kits out there they all have there problems but I think its fair to say there is no bad kit just some that suite one application better than an other. Regarding straight forward fitment for the most part it is straight forward but there is some machining of the casing to get it 100% right 👍

[@4272005]

Great video Paul, i'm really looking forward to the gearbox build videos. Are glass beads from vapour blasting becoming embedded in the gearbox casing, a worry?

[@HREIRL]

I hear a lot of hype about this from some of the bigger company's ...... honestly. After we vapour blast our casings we run them through a 4 hour cycle in an ultrasonic cleaner. if that dosent get any remaining grit out. no engine conditions in the wide earthly world is going to. our ultra sonic cleaner reaches temps of 105 degs and vibrates at in acess of 60khz if either of those conditions where created by your motor trouble far beyond micro glass particles would be your problem 😂

[@4272005]

@@HREIRL Thanks Paul, I thought it sounded a bit far fetched.

[@fitzysminis8166]

Just come across your channel and the knowledge and content is very interesting, i think us viewers would prefer to see a close up more POV style video with some better lighting so we can see what your talking about with a voice over? Just a thought 👍

[@HREIRL]

Thanks Ollie noted and we will see what we can do

[@demetrispatrikarakos5565]

Great information and advice as always. My question is about the possibility of matching a remote gearbox to an A+ block as I want to restore the original Innocenti 1001 remote gearbox to replace my current rod gearbox. Would be very involving or not advised? Thank you a lot.

[@HREIRL]

No its very possible there is a few things to watch out for but for the most part as long as you keep all the transmission housings together it will work 👍

[@franktaylor7617]

😎👍 🇺🇸 I've become an expert in all things Mini in the past several months. There is no one in my shop ( actually it's just me in my 2 car garage) that knows more about the Mini Cooper than me. If course I'm kidding. I've learned everything from hands on my own car and a multitude of videos. I'm a motorcycle guy so I'm somewhat familiar with a dog type gearbox. They have some similarities. I'm hoping to not need to repair/rebuild mine any time soon. I didn't notice a bit of mis-engagemnt when changing between 2 and 3. I assume the best way to preserve the gearbox is a smooth deliberant medium firm shift? Not a slow light pull on the shifter. It's a stock 1275 road car with (the best I can tell, an 1984 Metro motor. Not sure about the gearbox yet) non S motor but it is an S car. Judging by the badging, brakes and a few other things. My expertise is only within the 4 walls of my garage and doesn't apply to the outside world.😏 I guess my question is. What's the best way to prolong the life of the gearbox besides frequent oil changes and mindful driving. Any tips I may not be aware of?? Cheers from Seattle Washington area.

[@aussiebloke609]

Double-clutching should in theory preserve the synchro cone clutches the longest, as you're doing their job for them (it's also how you shift on really old gearboxes that were designed with actual _sliding gears_ instead of dog teeth or synchro cones.) The more you match those internal gear speeds yourself, the less the synchro rings should wear.

[@franktaylor7617]

@@aussiebloke609 Thanks for the advice. I've only actually driven it once and that was from the place of purchase to home. It drove and shifted ok although it was a bit of chore getting the shifting down. The throttle was hanging open a bit so I had to let off the throttle, toe up the pedal, push in the clutch and shift. Of course this was the first manual I'd driven in probably 15 years besides motorcycles. Then being RHD made it all that much more interesting.😁 I stopped on the way home and fiddled with the throttle and fixed the hanging open. One less task during a gear change. From day one. I've been continuously improving the car.it started with needing to replace a broken wheel stud. It hasn't ended. I'm replacing the heater core now. Getting very close to the end of things that need to or can be replaced. Should be in 75% better condition than on the day I bought it.👍 Although it will look almost the same.

[@HREIRL]

Good advice there from aussiebloke, the best way to prolong the life of an ayling gearbox is positive shifting, speed matching so very carefully listen to what RPM your engine is at a given speed in a given gear when shifting from one gear to the next try an obtain that speed an you should be able to shift with out a crunch 👍

[@aussiebloke609]

Paul - would it be a good idea to use an oil without friction modifiers (like motorcycle oil) in a Mini? Bike oils are usually without friction modifiers because they run a wet clutch which could slip otherwise - and I'm wondering if this would help the synchro ring grip the cone better since the Mini shares engine oil with the gearbox.

[@HREIRL]

It would be great for the synchro hubs but unfortunately very unhealthy for the cast iron friction components of the motor :(

[@aussiebloke609]

@@HREIRL I was afraid of that. Bummer. :-)

[@andrewbeedham910]

great video, thanks for explaining s/c boxes. I have to buy the complete inards for my box and i think it has to be s/c. I'm running a ford 1600 xflow on the mini gearbox and have been advised to go s/c as the standard won't take the torque. i don't know the torque figure of the engine but i know it is around 170bhp. the car is mainly for hill sprinting but i want to use it on the road. do you think i need to go s/c and is any one companies better than any other companies. i have looked at MED and KAD so far.

[@HREIRL]

Andrew you are most welcome. That’s a very interesting project. I think you will definitely need SC gear kit all right. Boy MED and KAD make a very good gear kit.

[@normanroach3390]

Can you fit a Manuel petrol pump to a 1275 mini without taking the engine out . Norman

[@ghostlyfrog9521]

When are we gonna get more Gretel videos!?

[@HREIRL]

Very soon My friend we are just making some space in the garage at the moment