Ludax
2 posts
Joined: 26/02/2005 22:11:32
Location: Qta do Anjo Portugal
S/C drop gears
I was looking for a S/C gearbox but many people advise not to do that because it becames harder to drive (to change the gears), so what do you think of S/C drop gears? Are easier to drive almost equal or better than the original? In this case a 1275 GT from 1975? Tanx
Posted: Sep 07, 2005 11:53 PM
chrispy61
51 posts
Joined: 08/12/2005 22:27:39
Location: Torquay United Kingdom (Excluding channel Islands)
drop gears
i have a 1098cc mini clubman but im using a gearbox from a 998cc. i want some strait cut drop gears but am not sure what i need to buy and if i can get them? i also have the original 1098 gearbox but im told u cant get drop gears for this engine and gearbox? cheers chris
Posted: Jan 04, 2006 09:52 PM
im rebuilding my gearbox and im at the stage of fitting the gear that fits on the 1st motion shaft, i want to replace it with a stright cut teeth item but do not want to buy the idler and primary gears yet. what shud i buy coz there is diffrent amout of teeth and do not want to get it wrong! its for normal road car so dont want to change ratio for quicker acceleration or anything. cheers
Posted: Feb 12, 2007 09:38 PM
mark
397 posts
Joined: 18/08/2005 14:01:28
Location: Hitchin United Kingdom (Excluding channel Islands)
There are basically 2 sorts a series and a+ series they are not interchangeable, and its determined by the gearbox and not the block
be prepaired to pay a few quid to sort out the end float of the primary gear when you change this drop gear
but worth every penny on the smile factor when you get it working
Posted: Feb 13, 2007 09:07 AM
yea i no all that already, that wasnt the question. my mate fitted straight cut drop gears without any shimming or anything just fitted with old shims and that was it.
Posted: Feb 13, 2007 07:40 PM
found the aswer i think its 24 teeth??
Posted: Feb 13, 2007 08:34 PM
Asad
1 posts
Joined: 12/04/2007 11:13:43
Location: United Kingdom (Excluding channel Islands)
Trannex SCCR Box and Drop Gears - Possibly for Sale
Hi,
I have a SCCR box and drops from a Metro Turbo I used to own. I was holding on to it incase I bought another MT, but now I think I have given up on that idea!
The primary drop gear has a slight surface scratch. The bush is good though.
the laygear is damaged however, and requires a new one and layshaft - should cost around £120.
Other than that the box is good. The diff was pretty new too. But I think I have a new crownwheel and pinion that I can throw in.
Im located in London, if anyone wants to have a first hand look at the box.
Let me know if you need any further info.
Judging by what these go for on ebay etc, I am initally looking around £400 as it is. That includes the Drops and new crownwheel and pinion
Thanks
Posted: Apr 12, 2007 11:30 AM
Woody Mk1
9 posts
Joined: 04/11/2004 17:10:51
Location: N.T. Hong Kong SAR
RPM Drops WHenever change gear underload
HI, Could anyone help to sort out the problem, whenever change gear underload, at 3600 upwards, the rpm drops and I am using a HIF44 with BDK needle, standard spring, woould the stronger yellow spring helps? filter is K and N, ST 731 cam with 1310 S eng, temp drops a little when timing is retarded to 14 degrees at 1000 rpm.
Appreciate any advise!
Alfred
Posted: Apr 15, 2007 01:53 AM
John
1948 posts
Joined: 28/05/2006 16:49:46
Location: cambridge United Kingdom (Excluding channel Islands)
id of thought it to be unlikly to be the spring yellow springs will reduce acceleration alot making it less resonsive on the throtal most likly making the problem worse. one way u can tell if the piston is moving up to the max at too low a rpm is to make a stick with one 8th of an inch devishions on and replace the damper with it. then at stationarry see what part of the needle is reached at differnt parts of the rev range. if it reaches richest before 5000rpm strounger spring is prob nessary. the mixture may just be too lean at higher rpm so power dies off. bbw has quite a rich top end might be worth trying. when it bogs down does it speed up if u pull the choke up slightly. if so its most likly leaning off either due to a weak needle (unlikly) or a lean needle (most likly)
Posted: Apr 15, 2007 08:42 PM
Alun Evans
16 posts
Joined: 07/03/2009 01:42:45
Location: llanelli United Kingdom (Excluding channel Islands)
Pre A-Plus Drop Gear Housing onto A Plus Block
Hi i am currently building an A Plus engine but the Drop Gear housing is damaged beyond use but i do have a very good Pre A Plus drop gear housing now i know that this pre A Plus housing has a much smaller idler gear bearing than the A Plus 3/4" diameter pin on the A Plus idler Gear but i was wondering is it possible to get the Pre A Plus housing machined to take the A Plus idler bearing or get the A Plus idler pin machined to fit the Pre A Plus Bearing or am i going to have to scrap the idea and shell out for a New casing. Any help would be greatly appreciated. Thanks in advance
Posted: May 04, 2009 03:43 PM
james finnigan
Joined: 08/08/2008 08:53:10
Location: colchester United Kingdom (Excluding channel Islands)
Roller Idler Bearing Fitting -Transfer/Drop Gears - Help!!
Hi, I am in the process of fitting Straight Cut Tranfer/Drop gears to my 1275 S. My gearbox is a remote pre A+, which means the idler hole in the gearbox and casing is smaller than later boxes. The idler gear holes have a needle idler bearings fitted in them and then the idler gear slots into these bearings. However!!!!, the SC idler has central roller bearings and the end shafts are the same dimensions as the the holes in the case and box. As such you do away with the needle bearings and the slot the idler gear directly in the hole. Here is where my problem is; Attempting to slot the gear into the gearbox casing it is as tight as hell, infact I would be suprised if it fits. I would be affraid of splitting the casing or Gearbox housing if forced in. Is it standard accepted practise to have to polish out the holes slightly to allow fitment???. I am 100% confident that the idler roller bearing is the correct part. I have also tried the idler roller bearing in 2 other casings and its just as impossible. So I am not adverse to lubricating it and taping it in with a rubber hammer or polishing the hole slightly larger, BUT WHICH IS IT ?? lol If you dont now the answer but may know a man/women that has fitted a roller idler bearing gear (PreA+Remote), please make contact.
I am in the process of fitting Straight Cut Tranfer/Drop gears to my 1275 S.
My gearbox is a remote pre A+, which means the idler hole in the gearbox and casing is smaller than later boxes.
The idler gear holes have a needle idler bearings fitted in them and then the idler gear slots into these bearings.
However!!!!, the SC idler has central roller bearings and the end shafts are the same dimensions as the the holes in the case and box. As such you do away with the needle bearings and the slot the idler gear directly in the hole.
Here is where my problem is;
Attempting to slot the gear into the gearbox casing it is as tight as hell, infact I would be suprised if it fits. I would be affraid of splitting the casing or Gearbox housing if forced in.
Is it standard accepted practise to have to polish out the holes slightly to allow fitment???.
I am 100% confident that the idler roller bearing is the correct part. I have also tried the idler roller bearing in 2 other casings and its just as impossible.
So I am not adverse to lubricating it and taping it in with a rubber hammer or polishing the hole slightly larger, BUT WHICH IS IT ?? lol
If you dont now the answer but may know a man/women that has fitted a roller idler bearing gear (PreA+Remote), please make contact.
Posted: Jan 23, 2010 06:59 PM
humin
Joined: 25/02/2007 21:25:13
Location: Gdansk Poland
Straight Cut Drop Gears 1:1 Mini Classic 1275 A+ engine
For sale Straight Cut Drop Gears 1:1 Mini Classic 1275 A+ engine NEW - NEVER USED kit includes: - S/C 24 tooth primary gear for 1275 engine - S/C 30 tooth idler gear for A+ boxes using the 7/8" shaft - S/C 24 tooth input gear price 160GBP + 15/20GBP (standard/express) international delivery http://cgi.ebay.co.uk/Straight-Cut-Drop-Gears-1-1-Mini-Classic-1275-A-engine-/150553599045?pt=LH_DefaultDomain_212&hash=item230db19c45
Posted: Jan 26, 2011 10:54 AM
stuart wood
Joined: 02/09/2015 08:12:36
Location: whiterashes United Kingdom (Excluding channel Islands)
Drop gears
Hi, I have a 1380 fast road engine fitted with straight box and drop gear set, the drop gears are 24, 31 , 24. The bearing on the idler gear failed and has damaged the shaft on the gear so it needs replaced.
All I can seem to find is 30 tooth options, will this fit or do I need to buy the whole matching set?
Many thanks
Posted: Jun 09, 2019 07:31 AM
Constant whining sound from engine!
nar, primary gear, or drop gear
Posted: Jan 08, 2008 08:36 AM
rozzer1275
70 posts
Joined: 20/08/2006 15:25:05
Location: harpenden United Kingdom (Excluding channel Islands)
Making an alarming noise
could be drop gears, lot of work just to check it.
Posted: Sep 29, 2008 01:11 PM
diff
i calculated if had standard 1:1 drop gears should be doing 57mph at 3000rpm if my calculations are correct. if u has a 1.1:1 drop gears this would give 52mph. speedo error is normally around 5% so if i was a gambling man id say ur drop gears are around 1.1:1 but u cant really be sure unless u have accurate averge speed eg from satnav. i wouldnt gear up up higher if u want it to accelerate espeshally with the work involved.
Posted: Apr 30, 2008 11:29 AM
pickme
672 posts
Joined: 08/09/2004 23:10:14
Location: Chippenham United Kingdom (Excluding channel Islands)
Straight Cut
You see figures for BHP at the flywheel and at the wheels and the difference is what is lost through the drop gears and transmision. Straight cut gears are more efficient than helical cut gears but the price you pay is noise. One the road, a straight cut box is basically pointless because the noise will drive you mad, but another area to look at is at straight cut drop gears. These transmit power from the engine down to the gearbox. Normal helical cut gears loose power for each gear and the mini has three drop gears so replacing these saves power without too much increase in noise. They also arent as expensive as a full straight cut set but are still pretty pricy.
Posted: Apr 08, 2005 06:14 PM
minicranks
3 posts
Joined: 13/09/2004 09:51:35
Location: Shannon New Zealand
popping out of 2nd gear
I have a similar prolem in my own car it drops out of gear on deacceleration and nothing wrong with my engine mounts. its coming out next week to have a look as new baulk rings and new 2nd gear was fitted, i will look at the springs under the 2nd gear syncro and also the selector fork to see for any wear, hope it comes right as it annoying as it doesnt drop cleanly out of gear but sounds like its drops in between and is running on the teeth. bugger.
Posted: Dec 22, 2004 04:44 AM
eh?
Do you mean the difference between SC and non SC drop gears? If so, the difference is that more power from the engine is transfered to the wheels because SC gears are more efficient than helical cut gears. Your drop gear bearings will last longer with SC too because the lateral load is all but but removed. The price for this improvement is the noise. It also sounds like youve dropped a spanner in the gearbox when the engine is idling out of gear. If you want the hear what they sounds like, go here - http://www.geocities.com/minivan1340/timed.wmv - this is a single lap of Curborough Sprint track followed by the return leg to the pits. The return to the pits is going to be more like normal driving, but youll get the general idea.
Posted: Sep 09, 2005 01:30 PM