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Kthomas #890872 09/16/22 6:52 pm
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1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Triumphs on eBay
Kthomas #890876 09/16/22 8:29 pm
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ah, the leaf spring blues . . .

iirc, i assembled the leaf spring gearbx in 5th? and then when you push the inner cpver on, it rolls into correct alignment?

maybe not. i hated that leaf spring. put a plunger in with buckshot's kit. doesnt shift any different but vastly easier to index


i'm old enough to remember when patriotism meant not trying to overthrow the government.
L.A.B. #890877 09/16/22 8:43 pm
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I don’t remember. It seems like I followed the instructions off of a website. I did it a long time ago.

Kthomas #890879 09/16/22 8:47 pm
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I bet I put a 4 speed plunger in there because I don’t remember even contemplating any plunger differences. I think I did change over to a plunger though.

Kthomas #890999 09/18/22 5:35 am
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Hi Kthomas, Was motor originally a 4 speed & you converted to 5 speed? Or prior owner started conversion.

Why I ask is the shifter shaft quadrant as well as the pawls in the quadrant are different between 4&5 speed. If you have these 4 speed parts in outer cover, it might shift on bench, but actually riding it will shift very oddly & you'll have tough time shifting to next gear. Identifying these parts is covered in the 4-5 speed conversion paper listed above by desco. Also make sure the curved centering springs are perfect & shifter centers reliably.

Generally, if you mis indexing installing inner cover, the shifter selects gears normally. But... You'll have a limited range of gears, depending on how far you missed correct indexing. The late 4 speed cam & 5 speed cam have same detent profile. So a leaf spring will work with both.

Leaf spring started later production 1970. The early year production so far as I can tell still used 1969 cam plunger (not leaf spring). This plunger has different shaped point to match early cam. Factory eliminated leaf spring on 5 speed T140 type 5 speed, which had reinforced gears & reverted to the plunger. The tip of 1973 plunger was reshaped to accommodate the shape of the leaf spring cam. So if you drilled case for cam plunger make sure you have correct late cam plunger.

If you drilled case, you can remove plunger & look up into hole & see cam. You can rotate cam with screw driver through hole, or finger if they're skinny as mine. You can turn cam & count the notches for plunger & verify the inner cover is indexed properly. You must really zig zag rear wheel to align dogs as you turn cam.

If you have correct 5 speed parts in outer cover & shifter centers well, & you still have leaf spring, it's time to pull outer cover. With cover off move the shift quadrant in inner cover with channel lock pliers. Again zig zag rear wheel a lot while shifting. You're seeing 5 tooth tops the pawls push on. Look at horizontal of the pivot shaft for quadrant. Shift all the way one way & all the way the other way. The last tooth should be centered on pivot center line in 1st & 5th. You'll feel leaf spring notch into cam & hold gear you've selected. If you missed cam timing you won't be able to go all the way. The shift fork peg in cam will stop in end of cam groove & you won't be able to move the quadrant farther.

I'll email you a few photos of what I'm talking about. When you are in 5th gear the top tooth on quadrant will be at pivot center line.
In 1st gear the bottom tooth will be on center line.
3rd gear will be centered.

Bikes with plunger is very easy to index. Leaf spring. Not so easy at all. But you can verify perfect indexing on bench by shifting using the pliers. I've never indexed a 5 speed with leaf spring.

Until you do a little diagnosis, you won't know what is wrong. Start by pulling outer cover & checking shifter shaft parts & pawls. Then shift with the pliers. You'll find problems is probably one or both of these.
Don


1973 Tiger 750
Kthomas #891002 09/18/22 7:10 am
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Note that I believe John Healey made a (rare) mistake in his article on 4 to 5 speeds, in that the index plunger listed for the early camplate is the later round nosed one, you need the T140 pointed plunger. I’m on holiday right now, so can’t give you the part number. Beware too that you can get a condition where the plunger housing can hit the camplate, or the spring go coilbound with the plunger hard against the camplate. These conditions only really come up when changing from 4 to 5 speed, or converting from leaf spring to plunger, but easily checked.
Hth

TR7RVMan #891020 09/18/22 2:30 pm
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It shifted like it was supposed to when I first put it together but now I can only catch a couple gears and there is no uniformity to the shifting at all. Thanks for everyone’s wisdom . I have printed off all the pertinent information and as soon as I can get motivated I’ll try and sort it . It’s probably something simple. I hope I haven’t trashed something in there by running it. These gears are getting expensive. I think it was originally a 4 speed because I think the main shaft was the only thing in the box when I got it and it was a 4 speed part (I think ) 72 Tr6r . I put the gear set in there at least ten years ago because I had the parts laying around and thought I would use the engine some day . It was so clean otherwise but the PO had no clue as to what he was doing and as I’ve shown neither did I 🤪

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Kthomas #891036 09/18/22 6:24 pm
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Hi Thomas, If you got all 5 gears & neutral on initial road test, indexing is good.
Your problem should be in outer cover.
4&5 speed uses same outer cover on right foot shift.
The 5 speed demands less lever travel as teeth in quadrant are closer together. So the V of pawl holder is wider to limit lever travel. The hook tooth of pawls is repostioned to accommodate this as well.

If you are really careful you can short shift the lever on 4 speed parts to select 5 speed gears. The cam can be felt as plunger notches in. This is sort of intuitive on the bench during testing moving lever by hand.

On the road your toe will over shift as your toe feels lever hit the stop. Not so easy to short shift lever on road with toe. At least not for me.

If you have correct parts in outer cover, but lever not centering reliable the pawls never stop at home position. Again by hand you can shift it better. By toe while riding is nearly impossible to center lever close enough to reliably get next gear. I have personal experience with binding laver shaft & bad springs as well. It will do odd things & drive you crazy. Sometimes will feel ok, then not.

Please look under trans & verify if you have plunger or leaf spring. I have detailed videos of how to index plunger type 5 speed correctly first time every time.
Don

Last edited by TR7RVMan; 09/18/22 6:25 pm. Reason: Changed sentence

1973 Tiger 750
TR7RVMan #891058 09/18/22 10:56 pm
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It has never shifted correctly on the road.
It felt as though it was shifting correctly using the rear wheel on the bench after I first put it in without oil

Kthomas #891076 09/19/22 12:39 am
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You will never figure this out till you know what's in the gearbox. Time to pull it apart and try to identify each part. Until then all advice is just guessing.
Good luck.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Kthomas #891110 09/19/22 5:52 am
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Hi Kthomas, Time to pull outer cover. Again, what do you have leaf spring or converted to plunger?
Don


1973 Tiger 750
TR7RVMan #891215 09/20/22 5:36 am
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Originally Posted by TR7RVMan
Hi Kthomas, Was motor originally a 4 speed & you converted to 5 speed?
Leaf spring started later production 1970. The early year production so far as I can tell still used 1969 cam plunger (not leaf spring). This plunger has different shaped point to match early cam. Factory eliminated leaf spring on 5 speed T140 type 5 speed, which had reinforced gears & reverted to the plunger. The tip of 1973 plunger was reshaped to accommodate the shape of the leaf spring cam. So if you drilled case for cam plunger make sure you have correct late cam plunger.
Don
Please excuse the hijack. I have a late '72 T150V. Parts book shows the leaf spring but I have the plunger. I never really looked at my plunger. What are the chances that I have an early plunger with a later quadrant, or vice versa?


"Gosh, it's not a 1/4 20, must be metric."

72 T120V cafe project "Mr. Jim"
72 T150V "Wotan"

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Kthomas #891216 09/20/22 5:52 am
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The reality is that almost anything can get mixed up in 50 years, but if you don’t have a problem, leave well enough alone, just making sure that oil gets changed (using EP 90 GL4 gear oil)

Kthomas #891262 09/20/22 5:39 pm
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Hi, The factory built 5 speed twins were marked with a V, so would read TR6RV, T120RV etc.
Did factory 5 speed have leaf or plunger on these bikes?

Starting in ‘73 all 750 got 5 speed & plunger. What about these late 650?

Finally the very last 650 had 3 row chain. What about these?

Back in the day, we rode 71 & 72 bikes all over the place. All 4 speeds. Transmission worked fine. My close friend had late 72 Tiger 4 speed with valve cover type rocker boxes. That was a great bike. 4 speed transmission worked good on it. We traded bikes sometimes. Did it have a plunger?
I serviced this bike a few years I never paid attention.
Don


1973 Tiger 750
Kthomas #891269 09/20/22 6:27 pm
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Hi Don,
I have two 1974 T120RV bikes.
They obviously have 5 speeds.
They also have the triplex primary chain and the 6 bolt tappet inspection covers and the front disc brake.
They have the plunger type gear indexer.
They are incidentally a great bike-- the front disc and 5 speeds combined with the revvy 650 motor makes for a great country road bike.
Highly recommended
Just my two cebnts worth of course.

Kthomas #891273 09/20/22 7:08 pm
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72 had and I think 71 had the leaf spring. I got rid of that at the same time I upgraded the gears (broke fifth). The five speed with that 650 motor is a joy on the twisty canyon roads. My 68 four speed sits a lot.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Kthomas #891308 09/21/22 1:46 am
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my T120RV DG 1972 OIF 650 had the early five speed, the leaf spring, duplex primary, four-bolt rocker covers.

i replaced the gearbox internals with those from a 71 that had the CP1000, and put in a plunger. needs a gasket now under the inner cover that it didnt need before.


i'm old enough to remember when patriotism meant not trying to overthrow the government.
Kthomas #891328 09/21/22 5:39 am
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My EG T120V has the leaf spring, my KG T150V has the plunger. I replaced the lay shaft on the T120V after the original broke, replaced the main shaft high gear and bearing too. The first-gear dog had already been upgraded. I replaced the lay shaft on the T150V just as insurance.
As for oil, the Trident was shifting a little hard on my last trip so I drained the oil. I did some research and it turns out that the Lucas gear oil I had in there is at the bottom of the list when it comes to being friendly to yellow metal. I ordered two quarts of Red Line Shock Proof on Amazon. A friend of mine with another EG T120V recommends it highly.


"Gosh, it's not a 1/4 20, must be metric."

72 T120V cafe project "Mr. Jim"
72 T150V "Wotan"

Kthomas #891539 09/23/22 1:05 am
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Hi DavidP, Please let us know what you think of the shock proof oil. What weight did you get.
I’m most curious to see if it actually makes a difference.
Don


1973 Tiger 750
TR7RVMan #891893 09/27/22 10:09 pm
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Thank you so much for all your help. My gearbox is sorted now and works great. It was the shift quadrant in the outer cover . I put redline gl4 spec 90wt oil in it.

Kthomas #891903 09/28/22 2:38 am
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Hi Kthomas, That’s great news!!
Exactly what did you do inside outer cover?
Did it actually have 4 speed quadrant? How did springs look?
What type pawls did it have ?
Thanks.
Don

Last edited by TR7RVMan; 09/28/22 2:45 am. Reason: Changed sentence

1973 Tiger 750
Kthomas #891955 09/28/22 10:55 pm
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I just took an outer cover off of a spare five speed and made sure it had the correct wider shift quadrant. I didn’t really inspect the springs. I guess I should have. I also replaced the gear selector quadrant in the inner cover as the teeth were better.

Kthomas #891963 09/29/22 12:07 am
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Hi Kthomas, Ok, so we don’t know why.
If possible when time permits it would be nice to know what was the cause(s).

This kind of information is very valuable to others that run into problems such as this.


Again, just when you have some spare time.
Don


1973 Tiger 750
TR7RVMan #891964 09/29/22 12:12 am
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It had a 4 speed outer cover on it with the 4 speed narrow shift quadrant in it. Wouldn’t that place the cam plate in the wrong position ?
I guess I need to figure out the pics. I do know that the plungers looked different also.

Kthomas #891973 09/29/22 5:39 am
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I remember the first time I indexed a 5-speed. All I had was a Haynes manual. The text was for the 5-speed, but the pictures were all of the 4-speed. I went with the pictures, sure enough I ended up with a 4-speed, no top gear. laughing


"Gosh, it's not a 1/4 20, must be metric."

72 T120V cafe project "Mr. Jim"
72 T150V "Wotan"

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