Forum

[Revband]

It was you earlier comment " quite a bit of material needs to be removed" which caused concern, if it is only 1mm that is not a lot and shouldn't cause a problem, but it has to be evenly removed from all the dogs and case hardening should not be needed, good luck with it,

[OldBoy67]

Hi Revband.

Sorry about my lack of clarity.

I thought the dogs (and the teeth) had to be hardend? If not required it would simplify the job a lot.

[vince]

Hi, although not available new our host do have complete 250 gear clusters in the used parts. Vince

[Revband]

Oldboy, The hardening on gears goes very deep into the metal removing a small amount will not cause a problem.

[Alan R]

Hi guys---just a wee bit of experience to help matters----I retired from the MoD ( Army ) Engineering a while ago now but we had a dedicated department for metal spraying and then re-grinding....This was mainly on Rolls-Royce 1,000 BHP Main Battle Tank engines ( Crankshafts and splined shafts )....plus other associated items.....Hi OLDBOY67, sorry but I don't have the contacts anymore or I could have it done for you, LoL....I mention this just to demonstrate that the process is widely known and in everyday use in many different Engineering applications so don't be disheartened, something WILL turn up I'm sure...

[OldBoy67]

Hi Vince
Unfortunately our hosts do have Crusader layshaft gear clusters on their used parts section, but the slider gear is part of the mainshaft cluster. These rarely appear for sale and the last one they had was for the 5 speed box.
Thanks for all the replies.

[Stupot65]

There is a basket case crusader on eBay at the moment with gearbox internals laid out.he may sell separately.its worth an enquiry.can do it for you if not a eBayist.Stupot.

[Bullet Whisperer]

HI OB, as Revband says, you can square the dogs up. I have done it a few times and before any self appointed 'experts' say you can't, I did it once at East Fortune on the Saturday evening of a two day race meeting when our 500 racer's 5 speed gearbox had been jumping out of 2nd and top gears. I borrowed a generator and a small angle grinder with a NEW disc, dismantled the gearbox and cut back the leading faces of the rounded dogs until they were flat again. Care needs to be taken to get them flat and straight - a brand new grinding disc is vital here - but you can use the wear as a marker for how far you need to go. My view was we were 300 odd miles from home, with no gearbox spares, so I might as well have a go. It worked and the 500 raced the following day, with no gearbox troubles. It is important to get all the dogs making contact with their partners at the same time, as you don't want all the load on one or two of them only, you might try a few trial assemblies of the gears on their shaft to check for contact, or lack of it, but it can be done. I also did it with a unit Redditch 350 Bullet where spares were unavailable and that worked out OK, too. Regards, Paul.

[OldBoy67]

Hi

Stupot - Thanks for alerting me to the ebay item. I think the guy wants to sells the whole lot as a complete project, but as you say no harm in asking. So I've contacted him.

Bullet Whisperer - I think you are right. The part I have is of doubtful serviceability in its present condition, so cutting the dogs may be the way to go. As you say I'm not sure how to ensure all three dogs mesh as one if I've been nibbling away at them! How to avoid partial meshing needs further thought on my part. The other reason I've been holding off is the question of hardening. Opinions on that seem divided. Some see it as vital, others are more relaxed. You describe your experiences well, but that is with a race bike, and longevity is not your primary concern?

Regards OB

[Bullet Whisperer]

Hi O.B., I must admit I didn't leave that gear in the race bike's gearbox for too long after that weekend, but it was used again a few times before I replaced the gear. When you consider the stresses a 45 bhp 500cc racing single puts on a gearbox, compared with a Crusader 250 road bike, it should probably last several thousand miles at least, before it starts jumping out of gear again. I found careful, light swipes with the grinder made a pretty even job, just give each dog the same number of swipes and you will be pretty near the mark. You can then assemble the gears on their shaft and use a very thin feeler gauge to check for contact, gear to gear, if you are uncertain they are equal. Regards, Paul.