PCSC Slipper clutch with Hostile spur mod

XREDRACERX

Well-known member
Messages
580
Location
So Cal
I tried a few different ways for quite a while to get my PCSC to be friends with the Hostile spur and I finally found what works.It's not an easy mod and I messed up my first time but the second two went easier.First I took my body hole reamer and reamed out both sides of the soon to be bearing hole on the spur.The inner race of the bearing needs to have no contact with the spur.So the hole needs to be just a little bigger.I used a 7/64 drill bit to carefully drill 4 holes around the outside of the newly reamed bearing hole on the spur.I marked the holes with red sharpie to find the spots with the most meat on them.The tricky part is you have to drill them close enough or the tops of the screws wont hold the bearing in.I used an exacto blade handle to hand start the holes.Then insert the bearing before finishing the holes with a drill or the sides will bulge and make your spur wobble a tiny bit.After the holes are done pull out the bearing and I used a 5/16 drill bit to carefully drill the tops of the holes to sink the screw heads below the plastic.I used 3mm x 8mm taper head screws.Put the bearing in and put the screws in.When I did this I did it slow in and out to cut the threads nicely. When done you may have to shave a bit more plastic with an exacto to get the screw heads to be level with the top of the plastic and the edges of the screws must touch the bearing to hold it in tight.Before you put everything together,you need to really clean the rubbers and inner spur and slipper carrier well.I used clorox wipes then let everything dry.It makes everything stay together really well.Put the carrier together with the spur and put the slipper assembly on your layshaft.I used the silver ring first, the washer, and the purple ring must be up against the bearing in the spur.I added the washer between the silver spacer and the purple one just to line up the spur and pinion gears nicely.
I've been using it this way for a little while now and I'm super stoked I can change gears now.It's a lot easier to have rubbers in each size spur instead of taking them out and putting them in the next size.It also takes a bit of weight off for racing balancing out my truck perfectly.Good luck guys and keep having fun!!!
 
Last edited:

XREDRACERX

Well-known member
Messages
580
Location
So Cal
Thanks, I just can't leave anything alone.lol It took me some time, a bunch of not so good tests, and a few different methods to get it right so I was stoked when everything worked out.Also if you look at my pinion gear you can see the groove wearing into it from the steel spur.It should last alot longer now.
 
Last edited:

Bajaball

Well-known member
Messages
117
How is traction on take off with the slipper can you still get out the gate good or is it a little sluggish just curious.
 

XREDRACERX

Well-known member
Messages
580
Location
So Cal
It's adjustable.You only want it to slip for a couple feet on take off.It helps with traction if you learn to adjust it well for the terrain, and it protects your drivetrain.
 

arthur daley

Well-known member
Messages
707
Location
Cornwall, UK
I tried a few different ways for quite a while to get my PCSC to be friends with the Hostile spur and I finally found what works.It's not an easy mod and I messed up my first time but the second two went easier.First I took my body hole reamer and reamed out both sides of the soon to be bearing hole on the spur.The inner race of the bearing needs to have no contact with the spur.So the hole needs to be just a little bigger.I used a 7/64 drill bit to carefully drill 4 holes around the outside of the newly reamed bearing hole on the spur.I marked the holes with red sharpie to find the spots with the most meat on them.The tricky part is you have to drill them close enough or the tops of the screws wont hold the bearing in.I used an exacto blade handle to hand start the holes.Then insert the bearing before finishing the holes with a drill or the sides will bulge and make your spur wobble a tiny bit.After the holes are done pull out the bearing and I used a 5/16 drill bit to carefully drill the tops of the holes to sink the screw heads below the plastic.I used 3mm x 8mm taper head screws.Put the bearing in and put the screws in.When I did this I did it slow in and out to cut the threads nicely. When done you may have to shave a bit more plastic with an exacto to get the screw heads to be level with the top of the plastic and the edges of the screws must touch the bearing to hold it in tight.Before you put everything together,you need to really clean the rubbers and inner spur and slipper carrier well.I used clorox wipes then let everything dry.It makes everything stay together really well.Put the carrier together with the spur and put the slipper assembly on your layshaft.I used the silver ring first, the washer, and the purple ring must be up against the bearing in the spur.I added the washer between the silver spacer and the purple one just to line up the spur and pinion gears nicely.
I've been using it this way for a little while now and I'm super stoked I can change gears now.It's a lot easier to have rubbers in each size spur instead of taking them out and putting them in the next size.It also takes a bit of weight off for racing balancing out my truck perfectly.Good luck guys and keep having fun!!!
Very nicely done, and a good how to guide, another 10/10 for thinking outside the box, definately one to go for if you swap ratios a lot, just keep one of each tooth count in the pitbox, ready to go at different tracks, well done, now all I need to do is buy a slipper clutch.
I suspose HPI would eventually sell more spur gear ratio's, but the weight saving doing it your way must be worth the work involved.
 

Outtaluck

Well-known member
Messages
130
Location
Melbourne Australia
Very good work m8, i was waiting for someone to mod the slipper clutch, I held of buying one because of that skinny spurgear + it was the wrong gearing for my use, you make me want to buy one now.....:drool:
 

XREDRACERX

Well-known member
Messages
580
Location
So Cal
Thanks Monsterman and Aurthur daley your a mad scientist yourself dude.I'm definately going to see if it holds up well Sat!I'll post the good, bad, or the aftermath of Phatoberfest.:ph34r:
 
Last edited:

XREDRACERX

Well-known member
Messages
580
Location
So Cal
Ok so here's the good, bad, and aftermath from Phat track.I didn't get any pics cause I was too busy eating tacos, hanging with cool people, and driving on the baddast track on the planet.So, I've run this with the normal 1 turn out setting for a while just fine and I wanted to test this out good so I set the slipper at 3 turns out and went out and hammered Phatdads whoops over and over for quite a while.When I pulled off the cover the whole assembly was smokin! So after everything cooled what I found was the modded spur held up great.The screws held the bearing in but they were loose.So I think in order for this too take a real beating I'll need the High temp spurs too keep the screws from backing out due to heat,and I think everything would be good.So all in all it worked and took a beating specially for being 3 turns out and spinning like mad.I think I'll go with the High temp spurs from now on.Since the slipper shouldn't be that loose I'll do some less extreme more regular settings and keep running it from now on.I did email Hostile and they said they might modify there molds in order for this conversion to be easier.
 

NOVA 71

Well-known member
Messages
124
If the slipper clutch is tighten down all the way would you need the 4 screws holding the bearing in place and why do you need to reem the hole out you can just leave out the one spacer and it sits on the pinion gear perfect. Has anybody tried this way,I was going to try it today but to much snow.
 

Loose Screws

Well-known member
Messages
52
Location
Dirty South
If the slipper clutch is tighten down all the way would you need the 4 screws holding the bearing in place and why do you need to reem the hole out you can just leave out the one spacer and it sits on the pinion gear perfect. Has anybody tried this way,I was going to try it today but to much snow.
The bearing has to be retained. While the bearing is held in place by the nut/spring the spur must be fixed onto the bearing or it will work its way off into it makes contact with the support plate...
 

jbooker82

Well-known member
Messages
2,204
Location
Nebraska
Yep the screws keep the spur gear from being pushed off the bearing. You need to open up the spur gear hole so the spacers make contact with the inner race of the bearing. I made a post in the Hostile section. They are supose to be doing a little work to the molds to include a little more material around the center bearing hole, and having the counter sunk holes molded in. That way PCSC guys just have to open up the back hole with a body reamer.
 

Carp Boyz

Well-known member
Messages
1,471
Location
Carp of course
Yep the screws keep the spur gear from being pushed off the bearing. You need to open up the spur gear hole so the spacers make contact with the inner race of the bearing. I made a post in the Hostile section. They are supose to be doing a little work to the molds to include a little more material around the center bearing hole, and having the counter sunk holes molded in. That way PCSC guys just have to open up the back hole with a body reamer.
does anyone know if Hostile did do something with their spur gears?

almost ready to install the slipper
 

Baja Guy

Well-known member
Messages
250
Location
Bay Area, Ca
Ive only tried the stock steel spur & plastic stock 57t spur without set screws on the bearing. Works great with no problems at all. I am curious to try hostile gears without the set screw mod. Reason for, is the slipper clutch spur gear holder has a beveled edge which looks to retain the bearing in its position without the need for set screws.
 
Top