classic motorcycle forum
Motorcycle Discussions => British Bikes => Topic started by: Andy_G on January 03, 2007, 10:08:37 PM
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I am trying to put my Bonnie G/box back together. Has anyone got three hands and long, ultra slim fingers? I could use you. Where should the camplate be on re-assembly? Haynes show a 4 speed box in the diagram, between gears but it looks nothing like my 5 speed camplate. I know LAB...buy the proper manual. I will as soon as I can but I would like the box together this week if poss. Thanks again.
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Look at the outside edge of the camplate as it is fitted in the box, you should count in a *clockwise* direction six notches, one large (1st), one small (neutral) and four large (2nd-3rd-4th-5th)?
The five speed box needs to have the camplate plunger set to the camplate neutral (small notch) position.
After installing the gear cluster, the inner cover needs to be fitted with the selector quadrant held in the position shown for the five-speed box in the Haynes diagram (well they got that bit right anyway!).
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You are a knowledgable guy, many thanks. I have the inner gearbox built thanks to you, now I have to fit the inner cover. You say the Haynes manual is correct regarding quadrant allignment but is that with the camplate still in the neutral position? There is hardly any info for the 5 speed box in my Haynes manual.
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Sorry I missed out an important piece of information. After fitting the gear assembly the camplate (five-speed only) then needs to be rotated to the *first gear* position (so turn the camplate clockwise) before setting the quadrant and refitting the inner cover.
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Okay, that explains things. That'll be a job for tomorrow. You are a gem, thanks again. You must be constantly checking this site, it's almost like 'I M' ing the speed you get back to me. If you want to look at the bike, you can visit my website on T140V.blinkz.com but please don't be upset, I bought it like that!
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Well, I have been busy today trying to get the gears to select. I haven't had much joy. I can get 1st, neutral and 2nd after a couple of attempts at setting up the quadrant. I have stopped for today because I can feel myself getting fed up with it. Previous experience tells me that I'll make silly mistakes if I continue. I set the camplate to 1st gear before fitting the inner cover and line up the second tooth of the quadrant with the centre of the gearchange hole. I tried it in the upper and the lower position, ie top of the second tooth level and bottom of the second tooth level with the centre line. Any suggestions?
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Difficult to say what the problem is working 'blind' like this.
Are you rotating the shafts as you try to select the gears? As it is unlikely that you will get all five sets of gears to engage otherwise.
When fitting the inner cover try letting the inner end of the quadrant to drop all the way down, and borrowing somebody else's advice"Offer the inner gearbox cover to the crankcase and lift the butterfly by 3/4 of an (internal) tooth. That'll then be in its 1st gear position."
If the quadrant was say, one tooth out either way I would expect that you would be able to select at least four out of the five gears by manually pushing the quadrant up and down by hand (as you turn the gear shafts). So possibly something is not assembled correctly in the
gear cluster?
If you contact me by E-mail (not PM -see letter icons to the left of this message) I will send you a copy of the assembly instructions from the factory manual.
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I'm off to try again with renewed vigour. I emailed you yesterday to say that the assy instructions from the factory manual would be most helpful. My email address is now included on my profile.
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Instructions sent, so hopefully you have them by now.
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Guess what? I now have 5 gears and a neutral thanks to you L.A.B. You were most helpful on this matter and I would like to thank you on this website. You are a gentleman and saint.
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Thanks Andy! Glad to be of some help! But credit must also go to Nigel (Vintagebike) for making it all possible by providing this great website!
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That's true. I'll feed back to him. If it wasn't for this site, I'd still be struggling.
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That's true. I'll feed back to him. If it wasn't for this site, I'd still be struggling.
what was the solution in the end anyway ?. ive expierianced similar problems with a trophy 650 , its a 74 and i presume (havnt got to 3rd) it has 4 gears .there seems to be some play in the camplate area and i thought it would be that but reading this i could have assembled it wrong , i opened it up originaly to stop an oil leak .the last owner said somthing about it not sitting right in neutral and the lever needing a little touch downward to get it right .
im thinking maybe i should have not bought the norton jubilee and bought a better trophy . ::)
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what was the solution in the end anyway ?
The four and five speed box assemblies are different anyway, so the five speed info isn't much good really (and could be misleading).
Although there is still a chance that the selector quadrant is mistimed to the camplate, which appears to be the cause of many selection problems.
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Hi L.A..B
I was reading with much interest the thread of a discussion on the woes of timing a 5 speed Bonnie gearbox. I too am in frustration :'(, I recently bought a T140V as a project with a recon gearbox in pieces to fit. I thought I had it right, got the MOT but only have 3 gears from the 5 and difficulty to engage. The manual and haynes give different methods to align the quadrant. I have the gearbox selected in first then align with the second tooth on the quadrant. I have tried above, below etc like Andy in the discussion thread.
Any help would be much appreciated
Paul
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Hello Paul,
I expect you have read through the messages above and there could be some info that will help?
The four-speed info given in the Haynes book isn't any help here whatsoever for the five speed box (or the late four-speed box either!)?
You said "the manual and Haynes" so do you mean you have a factory manual and a Haynes manual? If so then at least you should have the correct gearbox assembly instructions (build in neutral then select first etc.) then the inner cover should be offered up and the best way to set the quadrant position is to let it drop fully under its own weight, then as the inner cover is slid into position the *inner* end of the quadrant should be lifted -but by only a small amount (just enough to engage the first camplate tooth, that is apparently the best way to set the quadrant.
If that doesn't fix the selection problem then the fault could be in the selector mechanism somewhere?
But one thing at a time eh?
And maybe Andy_G could possibly offer some observations as he has had rather more recent experience of sorting this problem at first hand!
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Hi
Yes I have a workshop manual too and which has more detail. I built the gearbox in neutral and I seem to have all gears moving the camplate and rotating the wheel. but when I assemble the cover with first gear seleted and with the quadrant on the second tooth, I only get three gears. I have also tried various positions around the second tooth.
I bought the bike in bits and the last part to finish is the gearbox. I got my MOT last week with only three gears. (good job the gearbox does not need to work for the MOT and I only had to go a short distance). I thought I had all the gears before I took the bike for a test ride..
I have also changed all the springs in the plunger too. I think maybe I have got it right at some point but maybe I am waiting for a completly slick change box whilst it is oil free!
Thanks for the advice, I will give it another go. Its been a bit of a challenge.
Cheers
Paul
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You say you are only getting three gears?
Do you know which three gears?
Are you sure you are moving the camplate to the *first* gear position (rotate camplate clockwise as viewed from the rear of the motorcycle)?
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Hi
I think I got fourth with some force on the gear lever. Yes I believe I have engaged first rotating clockwise. First and second seem very smooth. maybe it is something to do with the selector for 4th and 5th. I have a recon gearbox. but the selectors are old.
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You said that you could select all the gears by rotating the cam plate. So the fault would seem to be with the selector mechanism (somewhere?)
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Hi, I recently had exactly the same symptoms when I rebuilt my Jubilee T140 5 speed gearbox - it was caused by misalignment of the quadrant. Here are some tips that I worked out after much trial and error.
a) Make sure you've got a way of turning the engine over; remove the index plunger and spring so you can easily move the cam plate to change gear; install all the gears. (Use lots of thick grease to hold bits in place if necessary).
b) Rotate the cam plate as far as it will go so that first gear is engaged. Make sure the cogs closest to the open side of the box are fully meshed together. Turn the engine over a few times to make sure the cogs are all aligned OK and that first gear is working.
c) Dont yet put the gastket or any goo in place.
d) Gently push the gearbox inner cover into place, with the quadrant hanging down under gravity. Just before the cover goes home rotate the quadrant so the inside part rises just a few millimeters - you should be able to feel the quadrant mesh as you push the cover home.
e) Do up the 3 retaining bolts/screws lightly.
f) Slip the clutch push rod into place and leave it so it sticks out about half an inch.
g) Replace the index plunger.
h) Using a long tyre lever or similar you can GENTLY lever the quadrant against the clutch push rod so it changes gear. You'll need to turn the engine over as you are doing this - preferably by rotating the rear wheel. Make sure all 5 gears plus neutral engage.
j) Once you're sure you've got the hang of it, remove the gearbox inner cover and refit in the same way only this time use a gasket!
I found the Haynes and Triumph manuals fairly unhelpful on this topic, but once I stopped trying to understand them and used the technique above it all fits together easily. (And works!).
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Thanks
I will give it a go tonight. I think the camplate is in the right position with all the gears, just timing the quadrant. As I have never had this bike running before (bought as a non runner), I have changed so many parts such as the clutch, it is hard to isolate the problem.
Cheers
Paul ;D
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And if you get the quadrant timing correct then you should be able to check the selection of all gears without the quadrant coming into contact with the either end of the slot?
When testing the gear selection I'm sure that I could move the quadrant just using hand pressure (whilst rotating the mainshaft etc. with the other hand) , with a piece of rag between my hand and the quadrant.
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I can find all the gears with a tyre lever but it is stiff, it is not exactly a gemtly levering to move the quadrant. I cannot move the quadrant with my hand. The quadrant does not touch either side of the slot. But when I install the outer cover the LH gear change is easy for 1st, 2nd, 3rd but difficult to find the other gears even whilst rotating the wheel and pulling on the lever. I am starting to wonder if I need to look at the selectors again. Maybe the 4th 5th selector is worn, or something is not lining up, maybe shafts?
I am getting somewhere as I have all the gears moving the quadrant. Wish it was RH change instead..
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Dismantle the box and check the selectors to make sure they are not bent. This shouldn't be as bad as it sounds as the gears come out in their clusters. Seems like you have had some really good advice and I cannot offer any better. Seems like my problem was slightly different. Good luck and thanks for the compliments on your email.
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Hi
I have looked at the selectors, they do not look bent but the lug which insert into the camplate looks chipped and worn on two of them (layshaft selector, not the main shaft 4th). The other thing that concerns me is I fitted a new clutch and belt drive and I may not of driven home the clutch hub as the main shaft to the gearbox has a lot of play pullng forward and tends to drift upward thus I have to push the shaft down to engage through the bearings of the gearbox cover. I seem to have good gear selction without the gearbox cover or quadrant engaged. Its a bit baffling. I will have another play with it.
;D
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I may of found the issue, I have worn lay sahft selectors (lobs that insert into camplate), however the camplate has heavy corrosion on the fourth gear indent. I have read before on forums that you can use a dremel to repair corroded camplates. Also on top of this I found small pieces of needle roller bearing from the rear part of the layshaft, probaby difficult to replace? At least the gears are new..
I have my work cut out to repair this.. summer is rolling on too.
I am starting to think it would of been easier to put the engine on the bench to work on or aquire a bike lift.
Thanks for all the advice
Paul
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You are most welcome although, I doubt I was much help to you. Come back if you have any more difficulties and of course, let us know if it works ok.
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Hi
I have changed the layshaft selector forks and cleaned the camplate but still find it hard to get the high gears, even by turning the camplate without the plunger or quadrant attached. I may need to replace the camplate which is a bigger job than I anticipated. At least I got the needle rollers back in..
I may look at the clutch first as the springs maybe too tight, not sure if this would casue it but you never know.
It certainly has me thinking...
Paul
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I may look at the clutch first as the springs maybe too tight, not sure if this would casue it but you never know.
I don't see how the clutch spring pressure could affect the gear selection (when the engine isn't running) but it must be remembered that the gears and shafts do need to be rotated either by turning the main shaft or the sleeve gear as the camplate is moved so that the gear dogs can engage.
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Hi
I have not pulled the clutch apart but loking at the gears again (I can now take them out blind folded) I am more convinced it is the camplate, Because I had to get new layshaft selectors due to the lugs worn and the plunger slots are corroded on 4th and 5th but looking at the grooves in the camplate they look more of a point in places, I thought they would be smooth. I have been searching for a picture of a camplate as the manual is not clear. To be honest I am more reluctant to change this as I will have to remove the main shaft. (probably why no one else has changed it)
I will have another play with it today.. but leave the clutch alone thanks..
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Hi
Looking at the camplate, dosen't look good so I decide what the heck pulled the clutch apart as I need to get the main shaft out to replace the camplate. Looking at the clutch hub I wondered if I pushed it on too far so the length of the mainshaft to the gear box was too short?
Decided to buy a run around on ebay so I have some wheels and do the Triumph justice in the rebuild than rush. The wife thinks I have bought another project. Gonna get banned from ebay..
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Hi
Looking at the clutch hub I wondered if I pushed it on too far so the length of the mainshaft to the gear box was too short?
I'm not sure that would happen.
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I got the main shaft and cam plate out.. The plate is really worn but the mainshaft looks fine, The main shaft is tapered so you are right the clutch hub cannot affect the length, I think I am clutching at straws due to frustration, sorry for the pun.. I tried to attached a photo of the cam plate but the picture is too big.
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Renew the camplate. If it is worn that badly it won't cause the selector forks to move enough to select the gears (I am presuming the wear has occurred in the grooves where the fork pins locate). All you can do is sysematically replace worn or damaged components until the problem goes away.