TTi Gearbox.

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storm42

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I pulled my (5 speed XHD) TTi box apart last night and thought there may be some interest in just what is inside these boxes. This one has done well over a 1000 miles of racing/parading and is in very good condition.

Interesting choice of country to source the layshaft bearing though, still, obviously good enough.

The reason for having a look inside was the amount of drivetrain play in the gears, now I have been in there, I am happy that this is through design and there is nothing wrong. It does explain why the box is so slick as well.

TTi Gearbox.


TTi Gearbox.


TTi Gearbox.


TTi Gearbox.




TTi Gearbox.


TTi Gearbox.


I have tried to show why there is so much slack in the TTi box compared to the AMC, the two following pics show the same gears and where they fit together for top gear from the two different boxes.

TTi

TTi Gearbox.


AMC

TTi Gearbox.


Much less slack in the AMC but because of the extra room the TTi has you get a much smoother gear change. I do realise the AMC box is pretty slick but the TTi is slicker.
 
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Great pics Ralph, thanks for posting.

It all looks as good as new in there.

What gear oil have you been using and are you sticking with it?
 
I found a post on another forum from SteveA and he posted this from an email from Bruce, I have done exactly what is recommended in the post and even found the correct oil, although this seems to be my last bottle, so I must find more as I will carry on with the regime.

the oil specs are as follows:
Use 330 ml of Redline Super Light Gear Oil 70W/75W GL-5, or Redline Weight Gear Oil 75W/80W GL-5 or similar spec oil. Do not use shockproof oils. Change oil after 5 laps, then again after 10 laps. Thereafter change oil after every second race meeting.

TTi Gearbox.
 
Two questions, firstly does any body know why TTI don't like shockproof oils, & what is the difference between the standard TTI 'box & the XHD?
 
I do not know Bruce's reasons but this site doesn't seem to like it. Go down to this bit: TRANSMISSIONS: ALL MITSUBISHI, V160, AND AZ6:
www://jackstransmissions.com/blogs/pages/oil-recommendations

As for the XHD bit, again I don't know for sure but I would guess that all the gears are just that bit bigger and stronger, obvious really but without a standard one to compare with, just a guess.
 
I have no idea where I heard it but I was told Bruce hated cleaning the gears & cases as the shock proof stuck like sh*t on a blanket lol
 
My 5-speed XHD came with the same oil recommendation text. Except that it said "Motul Gear 300 Oil 75W90 GL-5, or Castrol Syntrax 75W90 GL-5". Nice with alternatives.
One thing disturbs me though. It's a bit bigger, so it don't fit in a Manx. Hits the lower frame tubes. Well, after milling it a bit, it fitted. Not happy with that it has longer lever travel from 4th to 5th than for the other gears.
Main problem though is that clutch rod travel is to long. Gives a very hard clutch if you use the original handlebars with levers welded to the bars.
 
I think the fact that the box doesn’t physically fit the bike it’s sold for is inexcusable, and very annoying!

If your clutch is heavy cos it’s lifting too much, you can reduce it by putting a lever in the cable. Degens used to do this, especially when running Triumph clutches dry as less lift is needed when there’s no oil to clear. He used to make a simple reducing lever assembly and fasten it to the head steady. The cable from the handle bars would mount to the top of the reducing lever. Then he’d have a couple of positions where he could put the cable to the clutch so as to be able to adjust the leverage ratio. It’s very effective.

Devices are available off the shelf now it seems, though I’ve not tried one:

https://www.24mx.co.uk/easy-clutch-...u9RLosxriZuSvo-hoC13EQAvD_BwE&gclsrc=aw.ds#?p
 
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I know three different ways to fit it. The brutal way, using a big hammer on the frame to get the 3mm needed. Making new engine plates with the box a bit higher. Or countersink one screw for the inner cover a bit more and mill or file a bit on the inner cover.
Great to see the pics of the interior! The clutch mechanism reminds of the one in my CB250 racer. Could be possible to design one with less lift. But I think the Degen idea is far easier to make.
 
My 5-speed XHD came with the same oil recommendation text. Except that it said "Motul Gear 300 Oil 75W90 GL-5, or Castrol Syntrax 75W90 GL-5". Nice with alternatives.
One thing disturbs me though. It's a bit bigger, so it don't fit in a Manx. Hits the lower frame tubes. Well, after milling it a bit, it fitted. Not happy with that it has longer lever travel from 4th to 5th than for the other gears.
Main problem though is that clutch rod travel is to long. Gives a very hard clutch if you use the original handlebars with levers welded to the bars.

I believe there has been a couple of different clutch lifting mechanisms in the TTI, but if you have the 3 ball Triumph type, just fit 3 smaller balls.
 
Funny that, I just had mine apart. It is easy to work on. Using with the BNR clutch it has far more lift than necessary
for road work doesnt really matter.
It isnt cheap nor are the parts but quality remembered after the price is forgotten. Well not quite forgotten but you get the drift.
 
I believe there has been a couple of different clutch lifting mechanisms in the TTI, but if you have the 3 ball Triumph type, just fit 3 smaller balls.

Now that is written down and I have read it, I am not sure that would work, I have put mine back together so I cannot experiment now.

Maybe it would work, a smaller bearing would have to turn more to travel the same distance as a larger one, and as the distance of the bearing travel is governed by the clutch lever pull then the smaller bearing would not roll up the ramp as far and therefor not provide the same lift.

I need a drink.
 
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Funny that, I just had mine apart. It is easy to work on. Using with the BNR clutch it has far more lift than necessary
for road work doesnt really matter.
It isnt cheap nor are the parts but quality remembered after the price is forgotten. Well not quite forgotten but you get the drift.

I have forgotten how much mine was, I have to for sanity reasons.:D I also have a BNR clutch.

Did you have a reason to have a look inside? was there anything wrong? and is your layshaft bearing from India like mine?
 
I have have the Manx clutch, which have fewer plates than the roadgoing bikes. Don't need much lift. Reason not using a belt drive is that I wanted to keep the original badly dented chain guard. It got the dent's when the chain broke at the last lap at the Junior TT in -62.
 
The TTI uses a Triumph unit construction (650-750) type clutch actuator / lifter.

A PSP hydraulic actuator is available for these from LP Williams. These give a lighter lever action with a given spring pressure. But they give even more lift when used with the suggested 13mm maser cylinder.

So, I'm thinking that a PSP actuator with a smaller diameter master cylinder would give an even easier pull, and reduced lift.

Probably not a solution to someone wanting to preserve a '62 Manx, but might be a good idea for others...
 
I think the fact that the box doesn’t physically fit the bike it’s sold for is inexcusable, and very annoying!

If your clutch is heavy cos it’s lifting too much, you can reduce it by putting a lever in the cable. Degens used to do this, especially when running Triumph clutches dry as less lift is needed when there’s no oil to clear. He used to make a simple reducing lever assembly and fasten it to the head steady. The cable from the handle bars would mount to the top of the reducing lever. Then he’d have a couple of positions where he could put the cable to the clutch so as to be able to adjust the leverage ratio. It’s very effective.

Devices are available off the shelf now it seems, though I’ve not tried one:

https://www.24mx.co.uk/easy-clutch-...u9RLosxriZuSvo-hoC13EQAvD_BwE&gclsrc=aw.ds#?p

So technically you could use the device in reverse to increase lift?
 
I believe there has been a couple of different clutch lifting mechanisms in the TTI, but if you have the 3 ball Triumph type, just fit 3 smaller balls.

I have fitted 3 larger balls to one, you can easily measure that there is indeed more lift with the part in your hands, but have yet to fit it to the bike and test it!
 
I have no idea where I heard it but I was told Bruce hated cleaning the gears & cases as the shock proof stuck like sh*t on a blanket lol


We heard it from Brooking in NZ who got it from the horses mouth. It is on here somewhere that it was a pain on warranty work.

I have actually used the "Motul Gear 300 Oil 75W90 GL-5" since being in France...easier to get here than pretty much everything else.
 
So technically you could use the device in reverse to increase lift?

Yes. But with corresponding increase in lever pressure.

And you need to make sure it doesn't lift too far (same with your bigger balls) as there's only so much space available twixt lifter and end of mainshaft).

The PSP hydraulic lifter gives more lift, with lower lever pressure. If I needed more lift, and originality is no issue, this would be my choice.

I just fitted one to my T140, light lever action even with wound in springs, neutral easy to find - at a standstill - every time. Its never done that before...!

But I gotta ask... Why do you need more lift?
 
In answer to Storm42: A few weeks ago I was babbling on about gear ratios in low and over all ratio ie high gear. Despite the eye watering cost of a new low gear set that is what I sprung for and that is why it was apart. Best thing is you don't have to pull the box to do it.
The only other thing is all I've ever used is 80-90 or 85-90 gear oil. I suppose Ill got to 75- as specified. When I got the box nothing was said about the
oil. I will say the oil seems to get to all the bearings ball and needle so hopefully no harm done.
 
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