how do you change the spur gear??

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
S

swilsman

Member
Messages
9
i need to replace my spur gear. how do i do it, and what do i need to adjust the slipper clutch??
 
first you have to take the engine out...
next take the old spur gear off...
get a new spur gear
when u have a new spur make sure u put the pad on it (it comes w/ it)
install just like the old one came off..
tighten the nut all the way down, and then back it off after tightened..1/4 to 1/2 of a turn..

next drop the engine back in. set the motor mount bolts in place and then watch this SETTING GEAR MESH !!
 
savage x does a steel spur gear work any better? or will that just damage something further down the line??
 
Do you have the Savage X? If so I would just remove the six screws that holds the top of the tranny housing. There's no need to remove the engine. From start to finish should only take about 5 minutes
 
Just undo the 4 bolts on the motormount, remove the motor and put the new spur on....After you snug the whole spur down, I believe you back it off half a turn(I haven't had to change one in quite a while). Tranny or motor, either way you have to redo the mesh so it's just a matter of opinion. Stay with a plastic gear. It kind of acts like a fuse, instead of sending all the shock to the tranny.
 
I tighten mine all the way down..........no probs yet....
 
There may come a time when you say to yourself in Yogy Bear's voice, F%$k sliper clutches, BOOBOO! and go direct drive. I think I fully understand the principals behind the slipers application yet for my needs, the slipper clutch is more hassle than it's worth. This mod is not for newbies who don't know about the splipper's purpose and safety benifits. I think if you compete in full out racing and need slingshot exceleration while getting big air all day, then keep the slipper. Otherwize, why not check out the confidence one gets from having HP at the trigger rather that the slipper. The danger to the tranny is only present if land your jumps at a high rev which you should'nt be doing anyway. So don't do that!.... Now,.. I don't need to be dependant on splipper parts any longer and if I change my mind and need a slipper setup, I can simply swap setup's in 5 min. There's few things that compare to the hassle with a glazed slipper pad, a scribed slipper ring, or a melted spur gear hub. Just be sure that your flywheel nut is on tight with a tiny, tiny amount of blue thread lock on the shaft threads near the collet. Make sure that the blue doesn't get to the bearring behind the collet. If anyone wants to know how make thier own direct drive spur, Just ask and I'll post it.
 
Last edited by a moderator:
I'm sorry but I just spent close to two hours typing out a good discription of this mod and then I hit the wrong key by acciddent and POOF! it disapeared. I will have to reattempt this at another time. I promise to follow up on this fairly soon. Later,cobra.
 
Last edited by a moderator:
I Have the Savage 25... and an easy way to change your spur without removing the engine, it to loosen the hex screw that holds your carburator in place, and eighter twisting the carb to one side, or to remove it.

Just make sure none of the seals are damaged before you replace the carb, if some of the seals are damaged, just use some non hardening gasket on the middle of the carb neck.
 
OK, Cobra. I'm gonna make this discription in quick form to save a little time. After losing the last post I typed, I figure you or anyone else can post questions for any area's of my discription that need clarifying. To begin, get another spur gear w/ slipper pad, spur gear bushing, that little hex washer that goes up against the bushing, and the aluminum back plate for the slipper ring from your LHS. The reason for the this is that you'll have a back up spare in case you have any problems with getting this mod in place. Now remove the engine and spur gear assembly from the truck then set aside. What we are going to do is basically this: "Lock the spur gear to the back plate". If your good with tools persay, then this mod is about a 5 on a scale of 1 to 10. The important part to this mod is getting the spur gear and the back plate to be well-centered while being fastened securely using at minimum, two machine threaded bolts. You'll also will need to locate a tapping bit or two in case one snaps. (they are very easy to break at this size) they need to be matched to the size bolts I suggest. There is some room for variance here but, you want to sellect bolts that are not longer than the thickness (depth) of the spur gear/backplate assembly. In fact, I would suggest 1/8 in. shorter so there's less chance of any obstruction in the rotation path of the spur. I also recommend an 1/8 in. maximum size tap for this mod. Of course, if your going to proceed, your going to need to pre-drill the tap hole locations with a 3/32 in. drill bit so a tap can be used. Having a 12 in. long 3/32 drill bit about now, would be too cool because, you would be able to drill the pilot holes through the bulkheads while the new spur assembly is pre-mounted, giving yourself a perfect alignment and centering position for your tap locations. I used an extention w/ drill bit chuck. Needless to say, this is the way I recommend you tap the spur assembly but, knowing that most of us don't have a sellection of foot-long drill bits, I'll suggest a plan B later. But, first things first. The last thing we need is a small piece ( 2 x 4 in.) of sanding screen.(Having some extra screen is advised so you can have this reserved for other spur sizes that have there own assembly.) The screen is used to take up the thickness of the removed slipper ring, and provide a good bite against the spur. Step 1. Center punch two hole locations at apposing ends on the back of the spur gear. A 1/2 in. from dead center of the hub, inbetween the fins. Install the slipper pad into the spur gear like normal and set aside. Then, cut the 2 x 4 in. screen into halfs, making two 2 x 2 in. pieces. Now take one of the screens and trim it in to a circle, the same diameter as the aluminum backplate. Trim the other screen in the same way. Now trim screen 1 so it can lay flush with the keyed surface of the backplate. Both screens are going to need thier centers trimmed out to allow for the assembly to be slid on to the tranny's input shaft. Step 2. Place screen 1 on the backplate in the flush, keyed position as implied above. Then place screen 2 on to screen 1, and center it's position. This screen is optional and may make the spur assembly too thick. Don't use it if that's the case. The goal here is to create a spur asembly that is the same thickness as a normal slipper setup. Step 3. Install the pin for the inputshaft. Pickup the backplate w/ screen(s) and place the spur gear in position were it would normally be sandwiched against the backplate in your hand. Proceed to align the fins of the spur and the fins of the backplate, in a way to allow for the tap locations to be drilled without drilling through the fins. There is a position that will allow for two holes to be drilled. Now, find that position, and then slip the assembly on to the input shaft. Do this, while not letting go of the assembly. Now place the hex washer against the bushing and tighten up the spring with the nut. Back off one 1/2 turn from full tight. If the fins are still not in the position desired, Loosen the the nut enough to re-adjust fins if needed, making sure that the screen doesn't shift position, and return the nut to the prescribed tension above. Your now ready to drill pilot holes. Step 4. The locations of these holes arn't exactly critical but, keeping the bolt holes an equal distance from the center of the tranny's input shaft will help in preventing an imbalance to occure. I was able to use a drill extension with a chuck attatched on the end.This allowed me to drill pilot holes first and then tap each hole for the two apposing hole positions with a standard sized drill bit and tap. As mentioned earlier, I gained a good vantage point for drilling through the front bulkhead which is easier than pulling the tranny out for the mod. (If you have these tools in your service, then proform the method outlined above. If not, skip to plan B. now.) Now, remove the spur gear from the assemebly, and strip out the threads that you just created from the spur gear itself. DO NOT STRIP OUT THE ALUMINUM BACKPLATE THREADS. Now, re-assemble the assembly, insert the bolts, and tighten equally with red lock-tite. Now, install as per instructed and spin the spur gear on the shaft to see that it's NOT spinning out of round or woobley. IF IT'S OUT OF ROUND, YOU WILL NEED TO NEED TO TRY AGAIN at different hole locations until you get it right. Reinstall engine and set the mesh. Use blue thread lock on the motor plate bolts. YOUR DONE. PLAN B: As you probably know, there's more than one way to skin a cat, right? While holding the disscribed spur assembly in my hand, with the proper fin position in place, I was able to align the backplate and spur gear on to the input shaft and then carefully remove it so I could then clamp it in a vise or a c-clamp. Both clamping methods work fine but, I preffered the vice for that extra hand effect. While in the vise, I drilled one pilot hole and tapped it. After drilling the first hole and tap, I inserted a bolt to help maintain a locked alignment position while I reclamped and drilled the other ends pilot and tap. I then inserted the remaining bolt and installed the spur on to the shaft with the spring and nut as dirrected above and gave it a spin. As indicated above, "if it's out of round, you need to try again". If it's OK, then remove the spur from the shaft, disassemble the spur, and drill out the threads of the spur ONLY. DO NOT DRILL OUT THE THREADS OF THE ALUMINUM BACKPLATE. Reassemble and install the spur assembly back onto the tranny's input shaft, followed by the hex washer, spring, and tighten the nut one half turn back from full tight. I set the mesh and tightened the motor plate bolts with blue thread-lock. Now, I was good to go. Now here's where the extra screen material comes in. Make a dirrect drive spur for every size. And make an extra one in your favorite size incase you damage your favorite sized one down the road. There's nothing like having backups when you need one! And having differrent sized clutch bells are also par for the course....Now start her up! and GO! This Plan B method is not as precise as the first example but, it is the quickest. I've had good results in proforming this method. Sorry about no pics, and good luck.
 
Last edited by a moderator:
Thanks for the instructions. For the time being I've upgraded to the hardened steel spur gear. But this definitely looks like a mod I will have to attempt down the road a bit
 
No Problem, Cobra. I just wish I could have supplied some pics to make all that wording unnessessary. Oh well. Down the road, I'll post some attatchments to this thread and others will get it alot quicker with the pics. I hope I was clear enough, so far. later.
 
You must log in or register to reply here.

Latest posts

Members online

No members online now.
Total: 71 (members: 0, guests: 71)
Back
Top