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big joes or trenchers for a big block revo?

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Verry strange,as you should already know taller tires do the exact opposit,take from the bottom and add to the top,so your problem lies elsewhere,can you hear it hit second? Seems to me that's the issue,

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I figure the tires would cause it to take longer to accelerate and change the shift point, but the motor doesn't seem to be revving up to Max rpm. Full throttle seems like a casual half throttle cruise.
 
Hmm thats a stumper
When I put the x's my maxx I had to go down to a lower cb as I lost a bit of punch but once it got going look out:)
I'm currently running 22/54 and that seems to work well
Sounds like maybe a tuning or throttle linkage issue
I think with a bb you shouldnt have any issues pushing those wheels
 
ausher said:
I figure the tires would cause it to take longer to accelerate and change the shift point, but the motor doesn't seem to be revving up to Max rpm. Full throttle seems like a casual half throttle cruise.
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Is your throttle opening all the way?? I've ran these tires and love them your big block should have no issues with these.. Hmm it's weird
 
Yep first thing I checked. I'm gonna go with tuning for now until I rule that out. Last time I drove it was when it was 20°f out and I used a sock on the head. Today was 50°f so my tuning was way out of wack. .

Also are these tires directional? I noticed the tread pattern is opposite....
 
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thats got to be it, tuning issue cause you should tear it up with those wheels n tires:D
you could call them directional i guess looking at your pic you can move them around and get them all the same on your truck
 
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Could also be your slipper or clutch slipping. I know I had that issue on my savage when I gear too tall. Does fine in first gear, but the strain of second gear makes the slipper slip. I've never been able to overcome that so I run shorter gearing then the LRP can pull. Lots of wheelies... but saves me melting spurs.
 
I was thinking maybe clutch slipping, but wouldn't the engine still rev up max rpm on wot? Thought was slipper slipping so I tightened it up till it doesn't slip anymore.....
I got a 13t bell I'll try... maybe the 18t is too much...
 
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Yes your engine would rev up noticeably if the slipper was loose,
And a 13 t bell is way small dude,I Dnt think u will even b able to run that without grinding out the engine mount holes,
Sounds to me like your carb is not fully opening,.........
Please excuse my inability to properly read the above post that clearly says that you did check the carb opening,

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I got it tuned pretty good.today. its definitely not going into second gear. Probably due to the 18t bell and tires about an inch bigger in diameter.
 
The tranny shifts according to engine rpm,so with that said you are either not reaching that rpm,or the slipper is slipping,or something is wrong in the tranny,.......does it bog or cutout at the speed it normally hits second?

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it could of snapped the pin on the 2nd gear hub,mine did that when i first got the rb
took me ages to figure it out
 
ok. Took it apart and I don't think the pawl was engaging because when I hold the 2nd gear and flick the shaft with my fingers it wouldn't kick in. When I first assembled the trans with the robinson racing gears I could flick the shaft and the pawl would engage easily. I adjusted it so it engaged easier....
 
Took a look at the clutch. It looks like its wore quite a bit. Maybe it was slipping...
2013-01-22_01-34-07_541_edit0.webp


The bell looks like it has a lot of galling from the aluminum shoes...
2013-01-22_01-33-14_403_edit0.webp
 
ausher said:
ok. Took it apart and I don't think the pawl was engaging because when I hold the 2nd gear and flick the shaft with my fingers it wouldn't kick in. When I first assembled the trans with the robinson racing gears I could flick the shaft and the pawl would engage easily. I adjusted it so it engaged easier....
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unless you think you can flick that shaft upwards of 20k RPM's it shouldnt be engaging. If it is engaging when spinning by hand you will have no first gear and will basically be stuck in second gear.
 
That looks a lot like my clutch did when I fried it.
Clean up the shoes with a file & emery paper, you can get the alloy off the bell with diluted hydrochloric acid (get it from a pool supplier) & then clean up with emery.

I've found you need to clean up the shoes & bell every time you run it for the first few runs - the shoes don't have great contact untill they wear a bit, so they overload & gall a little to start with, once you have full contact they don't gall up as bad. Once they gall they will tear up the shoes pretty quick, so you have to maintain the clutch untill it's bedded properly.
 
I got plenty of that hydrochloric acid for our pool. I'm thinking of going with the buku clutch anyways. As far as flicking the shaft with.my fingers I just got to flick it fast enough to overcome the inertia needed to engage the pawl. Like I said when I installed the RR gears I could flick it hard enough to engage the pawl, but when I tried it this time it wouldn't. After looking at the clutch that probably is the problem...... but I could be wrong....
 
ausher said:
I got plenty of that hydrochloric acid for our pool. I'm thinking of going with the buku clutch anyways. As far as flicking the shaft with.my fingers I just got to flick it fast enough to overcome the inertia needed to engage the pawl. Like I said when I installed the RR gears I could flick it hard enough to engage the pawl, but when I tried it this time it wouldn't. After looking at the clutch that probably is the problem...... but I could be wrong....
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The second gear is engaged by inertia generated from RPMs. You can adjust this with the set screw but i highly doubt you can flick that shaft fast enough to get a properly adjusted hub to engage. It takes over 20k RPM for it to shift in your truck and I seriously doubt you can spin it that fast by hand.
 

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