SRX gear ratios

[Steve Lake]

now then.... #1's gearbox is in tatters (well 5th at least), I have several options, I have several 400 bottom ends and an xt600 bottom end.... question is, are the ratios wildly different, I'm assuming the xt will be, but hoping the 400's will be same or very similar, I seem to think, when I had a 400 lump in #1, that it felt like the gearing was the same....
any help from you wizards out there would be greatfully received ...
pip pip

[themoudie]

Aye Steve,

Sad! Lovely day and sitting in front of a screen doing techy stuff!    Just had a 1988 GSX1100 (Black/Red) in the workshop after it blew the baffle out of the backend, just down the road. A couple of self-tappers will hold it in place until it get back home to Fettercairn via Fort William!    Wall to wall BLUE, wi' a fresh breeze from the NE keeping it cool, just like home! 

Right, your ruddy gears mate. All this info is gleaned from Fowler's parts lists that are available online and I will download the links for each one so that you can make your own mind up. "Pinion" is the gear on the mainshaft (drive from crank), "Wheel" is the gear on the layshaft (drive to rear sprocket).

SRX 400 1988: Gear, 5th pinion (24T): Part Number: 2JT-17151-01 (Replaces 2JT-17151-00). Gear, 5th wheel (19T): Part Number: 2JT-17251-00 BOTH IN STOCK

SRX 600 1986: Gear, 5th pinion (??T): Part Number: 1VJ-17151-01. Gear, 5th wheel (??T): Part Number: 2JT-17251-10 (Replaces 5Y1-17251-00
PINION IS UNOBTAINABLE AND WHEEL IS BACK ORDER

XT600 1987: Gear, 5th pinion (24T): Part Number: 2JT-17151-00. Gear, 5th wheel (19T): Part Number: 2JT-17251-00 BOTH IN STOCK

So, IMHO it would appear that as long as you relace the gears as a pair, measure up with a micrometer to make "sure" and have a press with which to remove/replace the Gear, 2nd pinion from the mainshaft [firstly measuring the overall width of all the gears on the mainshaft and the internal distance between the 5th and 2nd pinions, as both are critical (can send specs if required/Speak to Slipstream)], I would give it a go. I used Slipstream to do the job for me and they supplied the pinion and wheel gears as well. As mentioned in earlier posts, the 2nd gear pinion can 'grip' then jump when being pressed onto the mainshaft and this means that it has to be removed and re-pressed until the overall gear cluster width and the internal distance between 5th and 2nd pinions are correct.

Fowlers_SRX400(3HU1-1988)_parts_list

Fowlers_SRX600(1XL-1986)_parts_list

Fowlers_XT600(2KF-1987)_parts_list

My regards, Bill

[Steve Lake]

Bill!!!!!!!..... you have surpassed yourself!!.... I hadn't considered that I might need a press, and tolerances were so critical, so.... maybe I should entrust the job to Slipstream if I were to repair the existing cluster.
however, it looks from the part numbers (and tinklers in Norwich confirm this), the long if the long number is the same then the 1jk/2jt/5y1 etc are indicative of the bike model number, and irrelevant... so I could replace the whole cluster (IF... I have a good set.)
least... that's plan A
plan B.... send cluster off for repair.... expensive no doubt

thanks for the comprehensive reply Bill...
Hope you are fairing well.... able to kick over Sally yet ?
pip pip

[themoudie]

Aye Steve,

Yes, Sally has been kicked over multiple times and taken for canters through the unusualy dry Perthshire countryside since last Saturday 19th May. A bit sore doing the deed, but 3 specific stretching exercises from the physio appear to make a difference and I am no longer louping along, but able to walk, straight and at a reasonable pace. Bit sore from the nerve damage after a bit, but it could have been a whole lot worse.

If I remember correctly the gears from Slipstream cost ~£120 + £50 labour + ~£12 P&P. As I have said before these machines are "No cheap", once you start taking them apart and having to use new parts and others expertise.

Give Martin a call after the Bank holiday and see what the craic is, or maybe speak to Stu or Andy at 'Steelcraft' or "SCR Classic Motorcycles" at Soham. Here is the link to their website: SCR_Classic_Motorcycles_website

Toodle pip, Bill

[Steve Lake]

Glad to hear you're back on the road, and continuing your improvement, excellent timing as the weather continues to be biker friendly 
Thanks for the additional info, especially SCR, I'd forgotten all about them, and well within a mornings round trip on #6, i'll be giving them a ring on Tuesday, see if they can take the job on.
my main problem at present is shifting the nuts on the balance shaft and crankshaft ... really need to get hold of a hammer socket driver, should be able to sort one out, friendly local motor engineer (yes, a proper engineer, old school, fix anything, has always looked after my sad procession of automobiles when it comes to MOT time, at 73 he's semi retired, but still loves to get his hands dirty, he must have the last remaining tin of original Rozalex in the universe  ), so will be round to his place on Tuesday to borrow said tool.
had any of these storms ? ... we only had a few rumbles of thunder and a few drops of rain.... but 30 miles away big floods etc, weird weather we're having!. I blame Brexit  .
pip pip

[themoudie]

Aye Steve,

Storms! What storms?    Nothing like that up here, once the harr has burnt off it has been wall to wall BLUE, with a cooling NE breeze. Yesterday, Edinburgh stayed under Mannin's Cloak and only reached 12⁰C, whilst across the Firth of Forth, Fife basked in 23⁰C+, as did we.

If you want to see real storms have a gander at the Maryland flash flooding videos posted today on Auntie BBC News.

I don't know what the timescale at SCR might be, as they also race Duke 250's and a RE Connie chair, along with other machinery! 

As for B....., "Tha's a lot a squit!"   

Always found wi' Rozalex that if you applied too much, small items tended to take on a life of their own i.e. migrate from the end of your fingertips!    Though it was good with hacks and cuts.

Toodle pip, Bill

[Steve Lake]

any help from you wizards out there would be greatfully received ...
pip pip

seventy three an I stil carnt spel !!!! 'greatfully'   .... wot a plonker !

[themoudie]

Nuf said! 

I'm no better and have to read everything through at least once and 'spell check' afore sending.

My regards, Bill

[Steve Lake]

Spoke to Martin @ slipstream today, he's pretty sure I can lift the cluster complete out of one of my 400's and fit into #1, the catch is, (so far) that the drive sprocket sits on a fine spline and secured with a nut (and presumably a lock washer), as opposed to #1's which is on a 6 segment spline secured by 2 bolts onto a lock washer.
the fine spline arrangement is apparently a later (& better) system, and are readily available.
the clutch basket is also on a finer spline, but I have the basket off the 400, in all other respects the basket is identical to #1's.
I have the 400 split and internals look and feel in great nick, so this weekend I will split #1, and A) survey the damage and B) find out if indeed the 400 internals will fit ok.
exciting eh 

[themoudie]

Aye Steve, this is sounding promising. I suspect the 400 shafts are the same as those on the XT600E as well. Here are images of Sally's layshaft splines, the XT600E layshaft splines, the tab washer and nut for the XT600E (N.B. the nut has a recess machined on its inside/against the tab washer to clear the splines on the shaft) and finally an image of Sally out for a canter at sunset last night.

My regards, Bill

[attachment deleted by admin]

[Steve Lake]

Bill. thanks for that.... spot on with the info, top pic is what I currently have ( martin sweet reckons this is the worst of the sprocket mounting methods), second pic is what I have just removed from my 400 bottom end (well, the splined shaft, I don't have the sprocket/nut/lockwasher ... but hoping these are readily available.... also hoping I can get a larger sprocket ... currently 16t on #1 (mind you, some may say that's why 5th gear got wrecked??)
Sally looking good, glad you're getting some good biking weather, has been fair to middling here too
pip pip

[themoudie]

Aye Steve,

Nut. Yamaha Part Number:90179-18552  £14-15 (inc VAT) Fowlers. All SRX 400 1988 (3HU) to 1990-1996 (3VN1/3VN2/3VN5) and same as XT600E 1990 3TB

Tab washer. Yamaha Part Number:90215-23265  £2-75  (inc VAT) Fowlers. All SRX 400 1988 (3HU) to 1990-1996 (3VN1/3VN2/3VN5) and same as XT600E 1990 3TB

On parts diagrams for the SRX400 1988 (3HU) to 1990-1996 (3VN1/3VN2/3VN5) there is shown a "collar" behind the sprocket. Part Number: 2NX-17462-00  £28-62 (inc VAT) Fowlers.

The sprocket on the parts diagrams for the SRX400 1988 (3HU) to 1990-1996 (3VN1/3VN2/3VN5). Part Number: 3GV-17460-10  £78-66 (inc VAT) "Back Order" Fowlers.

This collar is not shown on the XT600E 1990 3TB parts list and the sprocket appears to have a shoulder included in the casting. Part Number: 99999-01798 (15T).

The sprocket on the parts diagrams for the XT600E 1990 3TB. Part Number: 99999-01798 (15T)  £65-68 (inc VAT) "Back Order" Fowlers.

On Wemoto, sprocket for SRX400 upto 1988 (2NY), chain is '520' size, with the 6 spline shaft. From SRX400 1988 (3HU) to 1990-1996 (3VN1/3VN2/3VN5), chain is '480' size, with the multi-spline shaft. So the 16 tooth sprocket '520' size only fits the 6 spline shaft. Not your multi-spline shaft.

On Wemoto, sprocket for XT 600E 1990 (3TB), chain is '520' size with multi-spline shaft and available with 1 extra tooth giving (16T) and costs £12-92 + P&P + VAT. You'll have to check whether the collar is required for chain alignment! Link follows: XT600E_16tooth_front_sprocket_Wemoto_link

On Sally I went up 1 tooth on the front (16T) and then fitted an RD350YPVS rear (39T) up 2 teeth from the SRX original and a straight swap. This gives 70mph in 5th at 4,000rpm. It is only a wee change in ratio 2.44:1 (16:39), compared to the 'Standard' of 2.47:1 (15:37); whilst yours is 2.31:1 (16:37).

Hope this is as clear as the Great Ouse! 

My regards, Bill

[SRXpatriate]

Hello,

This collar is not shown on the XT600E 1990 3TB parts list and the sprocket appears to have a shoulder included in the casting.


This is correct. XT600E multi spline sprocket has additional shoulder and is to be fitted without the additional collar.

I would certainly not bother with the 480 size chain/sprocket and convert to 520 XT600E.

Rene

[Steve Lake]

Thanks Bill.... I just knew, as I posted the message about  the sprocket .... that you'd do your usual forensic search... .
can't believe the price of oem sprockets!

And thanks for the additional info Rene

couple of pics of different clutch basket splines


[attachment deleted by admin]

[themoudie]

Aye Steve and Rene,

Thank you for the compliment Steve, "Obsessive!" has been used.    And thank you for your confirmation Rene.

My regards, Bill