Search found 140 matches

by ampshire-og
Wed Aug 28, 2019 12:15 pm
Forum: Tech
Topic: Quaife or not ?
Replies: 3
Views: 253
Flag: England

Re: Quaife or not ?

It doesn't really matter whether you have a Quaife gearbox or not as NEB make a centre to suit the spline you have :thumb Regarding your gearbox do the gear pinions run on needle roller bearings? if it has then it's Quaife, if not it's another manufacturer like NEB etc but if your issue is just down...
by ampshire-og
Wed Aug 07, 2019 11:07 am
Forum: Tech
Topic: B44 to 82mm
Replies: 9
Views: 1100
Flag: England

Re: B44 to 82mm

Standard B44 liners will not bore to 82mm. I have seen standard liners not capable of being bored to +60" (81.5mm) without problems, they are just too thin or have been casted on the cock! New thick liner with crank cases being opened out is the answer if you want more CC. As for cams no change nece...
by ampshire-og
Tue Aug 06, 2019 8:42 pm
Forum: Tech
Topic: B44 to 82mm
Replies: 9
Views: 1100
Flag: England

Re: B44 to 82mm

82mm Omega Piston.
by ampshire-og
Mon Jul 08, 2019 12:02 pm
Forum: Tech
Topic: Push rod shimming
Replies: 7
Views: 1037
Flag: England

Re: Push rod shimming

Hi Aaronbsa,
I am doubtful as a competitor at Mortimer as I've injured in knee, however my son will be competing race no. 123 I am 124 and will be parked together.
I will doing the technical inspection in the morning, see you there.
by ampshire-og
Wed Jul 03, 2019 12:18 pm
Forum: Tech
Topic: Push rod shimming
Replies: 7
Views: 1037
Flag: England

Re: Push rod shimming

Part off in a lathe/make small washers/shims from old push rods and place under cap, that way you can make up the length of push rod you want :thumb but as a word of warning, I wouldn't go too mad on the thickness of shim. If you need a push rod more than say an 1/8 of the original I would obtain a ...
by ampshire-og
Tue Jul 02, 2019 12:28 pm
Forum: Tech
Topic: B44 to 82mm
Replies: 9
Views: 1100
Flag: England

Re: B44 to 82mm

82mm is well worth doing, I personally believe better than going to 84mm. If it's for mx the tracks we ride are generally small these dyas and plagued with tight corners, much better suited to a more forgiving engine. Also depends on the state of tune, the cam you use, the fuel type etc etc. I'm con...
by ampshire-og
Wed Apr 03, 2019 1:42 pm
Forum: Tech
Topic: B44 Inner Timing Cover Damage and Differences
Replies: 6
Views: 1029
Flag: England

Re: B44 Inner Timing Cover Damage and Differences

Inner timing covers are generally the same however have subtle differences. main difference being kick start bore for the B50 compared to the b25/b44. other differences are oil switch hole, rubber boot for points wire, circlip for oil feed seal for the B25, etc etc. Kommando is quite right about ali...
by ampshire-og
Fri Feb 22, 2019 7:07 am
Forum: Tech
Topic: BSA B25 relief ball valve questions
Replies: 2
Views: 886
Flag: England

Re: BSA B25 relief ball valve questions

If I'm correct the spring with the enlargement one end is for the oil feed side of the timing cover not for the blow off pressure valve. A straight spring is correct. :thumb
From memory and without consulting BSA reference books I think the overall length of the straight spring should be 5/8" (16mm).
by ampshire-og
Wed Feb 13, 2019 2:18 pm
Forum: Tech
Topic: B25 Big End Shells
Replies: 20
Views: 2134
Flag: England

Re: B25 Big End Shells

Thanks Both for replies, Yes Keith I would be very interested in your shells. I can wait until you get back to let me know what you have :thumb

Kommando thanks for the leads, unfortunately SRM are now down to LF Harris stock only. Will try Velocettes next.
by ampshire-og
Wed Feb 13, 2019 7:28 am
Forum: Tech
Topic: B25 Big End Shells
Replies: 20
Views: 2134
Flag: England

B25 Big End Shells

Frantically trying to get my B25 scrambles engine back together for the race season but cannot find any quality big end shells to purchase. My crank has been ground to -10 u/s but phoning around i.e. BBB, SRM, Britbits, checking the net etc etc I cannot find quality Glacier etc Triumph unit 500 shel...
by ampshire-og
Thu Feb 07, 2019 9:33 am
Forum: Tech
Topic: Best material for crankcase studs ?
Replies: 5
Views: 1236
Flag: England

Re: Best material for crankcase studs ?

EN8 is what you need. :thumb
by ampshire-og
Mon Mar 19, 2018 7:50 pm
Forum: Tech
Topic: Tight mainshaft to sprocket top gear
Replies: 33
Views: 5257
Flag: England

Re: Tight mainshaft to sprocket top gear

The solution I suggested I know for sure works, no reason why you couldn't fit a few more screws if your the nervous type or of course you could try another suggestion by the experts on here..... Oh maybe Not?
by ampshire-og
Mon Mar 19, 2018 1:44 pm
Forum: Tech
Topic: Tight mainshaft to sprocket top gear
Replies: 33
Views: 5257
Flag: England

Re: Tight mainshaft to sprocket top gear

This is a common occurrence with us scrambles guys that use the outrigger plate. To overcome this on quite a few engines I have carried out the following: Turn the outrigger plate shoulder down by 20 thou (0.5mm) or so (just so long as it lets the plate move to it's own centre) and refit. Rotate the...
by ampshire-og
Thu Mar 01, 2018 1:12 pm
Forum: Tech
Topic: better kickstarter for CCMs
Replies: 7
Views: 1713
Flag: England

Re: better kickstarter for CCMs

Terry Weedy makes the kickstarts and supplies the k/s shafts as well. Google him under terryweedy.com or averyproducts.com
phone no. 02380613690 plus 44 for UK.
by ampshire-og
Wed Nov 08, 2017 4:13 pm
Forum: Parts & Bikes wanted
Topic: b50 rocker box
Replies: 2
Views: 1067
Flag: England

Re: b50 rocker box

Hi David,
I definitely have a B50 rockerbox spare, can't remember if it still has the internals but will check.
Message me if you still need one.

Regards
Kevin
by ampshire-og
Thu Oct 12, 2017 12:53 pm
Forum: Tech
Topic: B50 MX sudden death!
Replies: 41
Views: 6470
Flag: England

Re: B50 MX sudden death!

Hi Jamie, Like your B50 it looks a nice one. Totally agree with Claus for checking what's what. My first try, would be to put some high octane fuel in the thing and gingerly give it a try out in a field. I wouldn't give it any welly cause it could all end in catastrophe! Once the (potential pinking)...
by ampshire-og
Thu Oct 12, 2017 12:32 pm
Forum: Tech
Topic: Air filter for 90s cheney Victor?
Replies: 4
Views: 1166
Flag: England

Re: Air filter for 90s cheney Victor?

I done away with those filters on my Cheney's as I was never confident they keep all the crap out! even though I did all the usual extra things, like grease the contact edge to form a seal etc etc. I made up an ally flange sealed and bolted to the inside of the airbox and bought a pancake type K&N w...
by ampshire-og
Thu Sep 14, 2017 4:12 pm
Forum: Tech
Topic: Another valve guide question
Replies: 20
Views: 3183
Flag: England

Re: Another valve guide question

It's the best way to go in my opinion.

Most good motor re conditioners should be able to do it for you.

I use a company in Winchester.
by ampshire-og
Thu Sep 14, 2017 3:38 pm
Forum: Tech
Topic: Chopped fins
Replies: 7
Views: 1552
Flag: England

Re: Chopped fins

yes there were/are, however appropriate machining of the head, barrel and piston can achieve the required results i.e. like 12:1
by ampshire-og
Thu Sep 14, 2017 12:32 pm
Forum: Tech
Topic: Chopped fins
Replies: 7
Views: 1552
Flag: England

Re: Chopped fins

What most road going riders only ever consider engines from their point of view, the reason why moto crossers remove fins is because their running on dope (methanol) which runs much cooler (and kinder) to the engine. Thus less finning helps keep the temperature up. :thumb there is the added benefit ...
by ampshire-og
Mon Dec 19, 2016 11:53 am
Forum: Parts & Bikes wanted
Topic: Wanted: B50 MX cam
Replies: 5
Views: 1206
Flag: England

Re: Wanted: B50 MX cam

I also have genuine new old stock mx cams been keeping for a rainy day that never comes. I assume your cases have the inner 3/4" cam bush.
by ampshire-og
Sun Dec 04, 2016 3:56 pm
Forum: Tech
Topic: JC CAM query
Replies: 3
Views: 804
Flag: England

Re: JC CAM query

Hi Mark,
Lift - cam/valve .356''/.390" (gross)
Tappet adjustment .005"

That's what's on the label.

Cheers Kevin
by ampshire-og
Sat Dec 03, 2016 5:45 pm
Forum: Tech
Topic: JC CAM query
Replies: 3
Views: 804
Flag: England

JC CAM query

Can anyone Help? Just picked up a new cam which come with radius followers, that looks very similar to a mega cycle cam. The paperwork and id on the cam is JC-250-15 racing camshaft, question is, what is it best used for? Mx or road race etc etc and what engine is it meant for? Timing figures are 41...
by ampshire-og
Tue Oct 04, 2016 1:00 pm
Forum: Tech
Topic: camshaft sealing
Replies: 15
Views: 2691
Flag: England

Re: camshaft sealing

A good two lipped oil seal works for me and i run the std bush set up in all my mxers.
I've seen Marks sealed bearing set up and i'm sure it will fix your problem.
The choice is yours.
by ampshire-og
Tue Sep 27, 2016 2:19 pm
Forum: Parts & Bikes wanted
Topic: WTB B44 VE or VS tank
Replies: 13
Views: 2475
Flag: England

Re: WTB B44 VE or VS tank

Hi Claus, Next year the classic motocross des nations is in randers denmark, so any goodies originating from the UK I would willingly transport FOC :thumb, trouble is its a year away! I have transported loads of parts to all the classic motocross events this year, 1st event included 4 sets of forks ...
by ampshire-og
Mon Sep 12, 2016 7:27 am
Forum: Tech
Topic: crappy fork gaiters
Replies: 32
Views: 4974
Flag: England

Re: crappy fork gaiters

I have exactly the same problem with a pair for my Victor Special. The bikes been sat in the garage most of the time during the six months. I believe they were made in Asia??? Last week went to a jumble and picked up a pair of NOS I think? They are a lot thicker with part nos moulded in the rubber, ...
by ampshire-og
Fri Jun 10, 2016 7:18 am
Forum: Tech
Topic: 68 B44 kickstart quadrant won't fit case
Replies: 2
Views: 684
Flag: England

Re: 68 B44 kickstart quadrant won't fit case

my guess is the k/s shaft has enlarged around the cotter slot. This happens over time as you tighten the cotter time after time. The fix is to gently file the shaft on the enlarged section of the shaft back to size, or if you have a lathe give it a gentle skim. If you open out the bush in the case, ...
by ampshire-og
Tue May 24, 2016 9:22 pm
Forum: Tech
Topic: bsa enduro/road cam
Replies: 2
Views: 821
Flag: England

bsa enduro/road cam

Can anyone tell me the profile differences between the b44/b25 enduro cam (usually marked with an 'e') and the road cam (usually marked with an 'o') ?
by ampshire-og
Wed May 04, 2016 12:38 pm
Forum: Tech
Topic: B44 Cylinder Query
Replies: 6
Views: 1531
Flag: England

Re: B44 Cylinder Query

To convert the B44 to 500cc most guys in the scrambling scene go to NEB who sale a piston having 84mm. The down side is, when the idea was first thought of, the pistons was based on a taller design, and they are still made to the same design. Just means you need a spacer under the barrel and replace...
by ampshire-og
Mon Feb 22, 2016 7:04 pm
Forum: Tech
Topic: LF Harris Conrods.
Replies: 52
Views: 8525
Flag: England

Re: LF Harris Conrods.

Either are good.
by ampshire-og
Mon Feb 22, 2016 4:16 pm
Forum: Tech
Topic: LF Harris Conrods.
Replies: 52
Views: 8525
Flag: England

Re: LF Harris Conrods.

From memory I'm using Glacier Triumph 5TA shells I got off ebay. Usually you can rule out the cheaper versions as these are generally the pattern ones. I think I paid £30 ish (inc. p&p) for two pairs. Triumph spares are always more plentiful. Before anyone says "what about the oil hole" in the rod (...
by ampshire-og
Mon Feb 22, 2016 8:22 am
Forum: Tech
Topic: LF Harris Conrods.
Replies: 52
Views: 8525
Flag: England

Re: LF Harris Conrods.

Thunder engineering all the way :thumb I use them in classic scrambling in a B25 dope motor with big valves trick cam, they can take the stick of additional horsepower!
Super quick service too! Spoke to Steve on the Friday and got the rod on the Tuesday, that aint bad!
by ampshire-og
Fri Nov 13, 2015 8:29 am
Forum: Project bikes
Topic: My B50SS project
Replies: 121
Views: 24330
Flag: England

Re: My B50SS project

I like that :thumb
what pump is that connected to the drill? I sure would like to give that a go.

Great post cheers
by ampshire-og
Wed Oct 21, 2015 12:33 pm
Forum: Tech
Topic: B25 Valve job
Replies: 15
Views: 2945
Flag: England

Re: B25 Valve job

Time for a new cam bush or don't bother with the cut down piece of case? ;-) only joking cracking idea :thumb Guess what i'll be making next! cos I aint got one of those!
by ampshire-og
Tue Oct 20, 2015 7:10 am
Forum: Tech
Topic: Main shaft bushing replacement?
Replies: 11
Views: 1897
Flag: England

Re: Main shaft bushing replacement?

Yeah that can happen skippy if the original tolerences are not maintained. From memory I think a new shaft comes out at 0.748" and bush to be reamed to 0.750" giving a 2 thou oil cushion. :thumb But i would double check the sizes as i'm working from memory.
by ampshire-og
Mon Oct 19, 2015 12:13 pm
Forum: Tech
Topic: Main shaft bushing replacement?
Replies: 11
Views: 1897
Flag: England

Re: Main shaft bushing replacement?

The two bushes you refer to are an interferrence fit in the high (sleeve) gear and has the mainshaft running through them in the as fitted position. The only way to exchange them is as Minety posted, gearbox out, then remove the sprocket to enable the high gear to be removed. Once out drive out the ...
by ampshire-og
Thu Oct 08, 2015 7:21 am
Forum: Tech
Topic: big end
Replies: 11
Views: 1941
Flag: England

Re: big end

If theres no up and down play i would have thought the radial clearances are fine and accecptable. However if you have excessive side to side rock I understand your concern. This suggests the journal is going barrel shape. The problem with this is when the rod is at Bottom Dead Centre does the side ...
by ampshire-og
Mon Oct 05, 2015 12:30 pm
Forum: Tech
Topic: crank bearings
Replies: 14
Views: 3575
Flag: England

Re: crank bearings

Checked my brand new pair of B25 crankcases I keep on the shelf and with the original bearings still in place, they are NOT marked up as C3. I am a mechanical enginner and cannot understand why you would want bearings with additional internal radius clearance fitted in an engine?Granted the bearings...
by ampshire-og
Tue Sep 29, 2015 7:19 am
Forum: Tech
Topic: crank bearings
Replies: 14
Views: 3575
Flag: England

Re: crank bearings

Taken from a bearing supplier catalogue: C3 bearings are bearings that have an additional internal radial clearance to cope with high speed environments where excess heat is generated. They are not suited to environments where critical alignment is required from the onset e.g. Where blades and cutte...
by ampshire-og
Tue Sep 22, 2015 7:12 pm
Forum: Tech
Topic: Rear shocks & exhaust pipe
Replies: 9
Views: 1893
Flag: England

Re: Rear shocks & exhaust pipe

Hi, Terry Weedy of Avery Products can sell you a front pipe B50 or B44. Originals being 1 3/8" Dia or he does 1 1/2" Dia for comp work. His number is 02380613690.
He has a very good web site too. :thumb