1/32 Wheel slip

Hello been building two RC battery powered Wainwright c class locos but I’ve have to split the cranks to allow the loco to go round the curves I have.
The issue is that despite adding weight to the locos I am getting wheel slippage on the powered axle causing the split cranks to bind. Doesn’t happen every time about 3 out of ten times it pulls away.
Anyone got any ideas on how to cure this?
 

Attachments

  • 3A0DC38E-075D-4EDF-A7E1-6B2A3670A7EC.jpeg
    3A0DC38E-075D-4EDF-A7E1-6B2A3670A7EC.jpeg
    126.8 KB · Views: 63
  • B2FA4C25-52EA-404B-B9EB-E334BEAF98E0.jpeg
    B2FA4C25-52EA-404B-B9EB-E334BEAF98E0.jpeg
    205.2 KB · Views: 61
  • 900EFCCB-554F-4345-842D-243800481539.jpeg
    900EFCCB-554F-4345-842D-243800481539.jpeg
    172.6 KB · Views: 59
Top