rrt2 layshaft end float

[berger]

i have not been to the pub, after successfully negotiating the oil hole conundrum line up with the needle rollers for the layshaft I have just done extensive forum research on layshaft end float and at the same time come across anji's interesting travels.  . it seems A65's is a common 3 to 5 thou so this is what I am going for even though there is some mention of 10 to 20 thou on other bits of reading on other sites. the sleeve gear has only one oil hole drilling and I can't get oil to the rollers through that hole. it may be it is one of those without the oil hole but I am NOT going to try and take it out risking damage whilst doing so because bush and bearing are ok. it is common when on the side stand for oil to creep down the main shaft and this will have the srm oil seal nut fitted retaining any oil creep- I will see one day question is those of you who run rrt2's have you got any disagreement on the end float and if so what do you set yours at so I can get it all together and put away to rest with its other bsa friendly parts. thankyou for listening, at this rate my pub will be shut from lack of funds

[Swarfcut]

bergs.  Methinks that box won't spend much time in the intermediate gears, so that needle race in the sleeve gear will survive just fine. You could pack the rollers with grease just to start with. Never seen a roller bearing of that type with an oil hole in the outer, but they must exist?

 Swarfy.

[berger]

swarfy yes the older Torrington ones all had oil holes and from looking on them some made in England some America. the ones more prominent for sale nowadays don't have the hole but as you say I will just help the bush and bearing out by putting a bit of grease in the sleeve gear recess [ gap between bush and bearing] and on rollers.

[chaterlea25]

Hi Berger,
The A65 needs tight tolerances to achieve good gear selection,
Pre unit clearance, is around 10 thou
Up to 20 Is ok

The layshaft is hollow and has cross drilled holes near the middle
This will allow plenty oil to the bearing
Grease can block small oil holes so I would avoid it

Did you manage to get the crowded needle bearing?
These have a much higher load capacity than the caged version

John

[berger]

hi john I have fitted crowded needle rollers for the layshaft with oil holes. the sleeve gear crowded roller is what we are on about now. I had a look on net and noticed some rrt2 sleeve gears have the 3 holes drilled in them like the STD ones. mine has one hole and I can't get oil through it to the rollers, I don't know if it was put in off line or if it is a later one without the hole but it is staying put. There will only be grease in the gap between the roller and bush. Thanks for information about the A65 box so what you are saying is the RRT2 copes with 10 to 20 thou? if so I will get to as near 10 thou as possible, while messing today I found out that the mainshaft kick start thrust washer was soft compared to the three layshaft ones. [ maybe to be expected with people using and losing bits over the years] I have sauced some on evil bay---- see what they are like! its a pity you can't harden mild steel washers.

[chaterlea25]

Hi Berger,
OK , sorry I misread your post
I need to go and look at my RRT2 box that's in bits to see which and what I have
I have a new sleeve gear from Autocycle Eng. and the oil hole bearings that I got from a friend in USA
As it always seems that every gearbox I get is worn out
I am intending to fit a STD first gear pair and have these and matching STD 3rd gear pair so the dogs will engage
but I also have a modified A65 1st gear pair

If you think of how little lube a 2 stroke big and small end needle bearings get?, I am fairly sure the BSA will be OK
Can you read the numbers / lettering on the sleeve gear roller bearing?
it will have "OH" afer the number if it has the drilled outer

John

[RDfella]

You can harden mild steel - only not by through-hardening. You'd need to get a can of case hardening compound (around a tenner).

[berger]

hello john thanks for reply, the two stroke bit makes sense as some time ago my engine ran on mist[long story been covered]. I am new to rr boxes never been in one until now, the sleeve gear roller is stamped B1314 Torrington made in USA NX . the blind layshaft one I can't remember and i have fitted end cap on but this one has the hole. the other layshaft one is stamped B1212 Torrington made in England, it has the hole but not stamped OH, so that is a mystery if OH means oil hole. I also have 26t A65 gear [layshaft[ matched with a 17 off of another layshaft machined to clear the ally in the sandwich case where the ball race fits. just to clarify even though it is needle roller layshaft the end float is ok at a larger setting than the A65? cheers

[berger]

RD fella yes casinit or something like that, but not as satisfying as having some decent carbon content . I have ordered some washers off flea bay and will compare them to the originals I got with the box cheers

[chaterlea25]

Hi Berger,
Here is a link to an article that details the thickness of the gearbox thrust washers
http://www.britbike.com/forums/ubbthreads.php/topics/713333/pre-unit-transmission-info-swing-arm-models#Post713333

Magnetoman has posted at length on the rebuild of his SCT2 on his 1957 Spitfire thread
these have the same bearings as the RRT2

On two previous gearbox builds I did with needle roller mainshafts I found negative clearance when the sandwich plate was bolted up,
"Drop some sockets or pieces of tubing over the 4 main studs and pinch up the nuts when the plate is in place to simulate the outer cover in position, then check the end float
Fitting a second gasket between the case and plate solved the problem
Access to a surface grinder would be nice 

John

[berger]

with you john mine is other way got to lose 30 thou even after having a gasket bolted up over night its got all proper thickness washers installed 108 ---93----- 113 thou .so really I have to lose 20 to give it 10thou end float, so my way of thinking is to take out the 113 and put two mainshaft washers together two times 68 thou =136  between 26t gear and needle roller in sandwich plate and that should work out at 7 thou end float. can't wait for washers from flea bay now , as they say nowadays EXCITING times ahead ---- I hope depending on the thickness of the two washers.my brain hurts

[duTch]

 A probably not- So- ideal way to do it may be to press the 'B' gear so it's 20 thou closer to the end of the shaft which puts it away from the circlip a bit - but there's no way to be sure it may not move back to the circle and end up with the same issue... having said that, some people are happy to not use the circlip at all 

**edit.... it may also affect the alignment of 'G' and 'H' gears by same amount

 **extra edit; ..... or the dog engagement of 'F' and 'H' gears

[berger]

holla dutch I thought of that and then thought not! so I will see what turns up in the post- another way of doing it a bit is to omit the gasket  or skim the main case---- not

[kiwipom]

hi guys, do any of you gearbox guys know the selector plunger thread size it is a very fine thread, cheers

[muskrat]

G'day kiwipom.
Do you mean the cam plate plunger housing thread? It's 5/8 x 20 I had to buy a tap only a few months ago.
Cheers