diff --git a/src/BulletDynamics/Featherstone/btMultiBodyConstraintSolver.cpp b/src/BulletDynamics/Featherstone/btMultiBodyConstraintSolver.cpp
index 68ba8d68f..c8f7fb0aa 100644
--- a/src/BulletDynamics/Featherstone/btMultiBodyConstraintSolver.cpp
+++ b/src/BulletDynamics/Featherstone/btMultiBodyConstraintSolver.cpp
@@ -26,7 +26,6 @@ subject to the following restrictions:
 
 btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btCollisionObject** bodies ,int numBodies,btPersistentManifold** manifoldPtr, int numManifolds,btTypedConstraint** constraints,int numConstraints,const btContactSolverInfo& infoGlobal,btIDebugDraw* debugDrawer)
 {
-	printf("btSequentialImpulseConstraintSolver::solveSingleIteration\n");
 	btScalar leastSquaredResidual  = btSequentialImpulseConstraintSolver::solveSingleIteration(iteration, bodies ,numBodies,manifoldPtr, numManifolds,constraints,numConstraints,infoGlobal,debugDrawer);
 	
 	//solve featherstone non-contact constraints
@@ -39,7 +38,6 @@ btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btColl
 
 		btMultiBodySolverConstraint& constraint = m_multiBodyNonContactConstraints[index];
 		
-		printf("m_multiBodyNonContactConstraints resolveSingleConstraintRowGeneric\n");
 		btScalar residual = resolveSingleConstraintRowGeneric(constraint);
 		leastSquaredResidual += residual*residual;
 
@@ -48,8 +46,7 @@ btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btColl
 		if(constraint.m_multiBodyB) 
 			constraint.m_multiBodyB->setPosUpdated(false);
 	}
-	printf("featherstone normal contact\n");
-	printf("numContact=%d\n", m_multiBodyNormalContactConstraints.size());
+
 	//solve featherstone normal contact
 	for (int j0=0;j0<m_multiBodyNormalContactConstraints.size();j0++)
 	{
@@ -60,7 +57,6 @@ btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btColl
 
 		if (iteration < infoGlobal.m_numIterations)
 		{
-			printf("featherstone normal contact resolveSingleConstraintRowGeneric\n");
 			residual = resolveSingleConstraintRowGeneric(constraint);
 		}
 
@@ -72,7 +68,6 @@ btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btColl
 			constraint.m_multiBodyB->setPosUpdated(false);
 	}
 
-	printf("featherstone frictional contact\n");
 	//solve featherstone frictional contact
 	if (infoGlobal.m_solverMode & SOLVER_USE_2_FRICTION_DIRECTIONS && ((infoGlobal.m_solverMode&SOLVER_DISABLE_IMPLICIT_CONE_FRICTION) == 0))
 	{
@@ -163,7 +158,6 @@ btScalar btMultiBodyConstraintSolver::solveSingleIteration(int iteration, btColl
 			}
 		}
 	}
-	printf("end featjerstp\n");
 	return leastSquaredResidual;
 }
 
@@ -209,19 +203,6 @@ btScalar btMultiBodyConstraintSolver::resolveSingleConstraintRowGeneric(const bt
 	int ndofA = 0;
 	int ndofB = 0;
 
-	printf("c.m_solverBodyIdA=%d\n", c.m_solverBodyIdA);
-	printf("c.m_solverBodyIdB=%d\n", c.m_solverBodyIdB);
-
-	printf("c.m_multiBodyA=%p\n", c.m_multiBodyA);
-	printf("c.m_multiBodyB=%p\n", c.m_multiBodyB);
-	printf("c.m_jacAindex=%d\n",c.m_jacAindex);
-	printf("c.m_jacBindex=%d\n",c.m_jacBindex);
-	printf("c.m_deltaVelAindex=%d\n",c.m_deltaVelAindex);
-	printf("c.m_deltaVelBindex=%d\n",c.m_deltaVelBindex);
-	if (c.m_deltaVelAindex>500)
-	{
-		printf("???\n");
-	}
 	if (c.m_multiBodyA)
 	{
 		ndofA = c.m_multiBodyA->getNumDofs() + 6;
@@ -558,13 +539,7 @@ void btMultiBodyConstraintSolver::setupMultiBodyContactConstraint(btMultiBodySol
 		}
 		const int ndofA  = multiBodyA->getNumDofs() + 6;
 
-
 		solverConstraint.m_deltaVelAindex = multiBodyA->getCompanionId();
-		if (solverConstraint.m_deltaVelAindex>10000)
-		{
-			printf("????????????????????????????????????????\n");
-			printf("solverConstraint.m_deltaVelAindex==%d\n", solverConstraint.m_deltaVelAindex);
-		}
 
 		if (solverConstraint.m_deltaVelAindex <0)
 		{
@@ -1682,13 +1657,11 @@ void  btMultiBodyConstraintSolver::solveMultiBodyGroup(btCollisionObject** bodie
 	//printf("solveMultiBodyGroup start\n");
 	m_tmpMultiBodyConstraints = multiBodyConstraints;
 	m_tmpNumMultiBodyConstraints = numMultiBodyConstraints;
-
-	printf("m_tmpNumMultiBodyConstraints =%d\n",m_tmpNumMultiBodyConstraints );
-	printf("solveGroup\n");
+	
 	btSequentialImpulseConstraintSolver::solveGroup(bodies,numBodies,manifold,numManifolds,constraints,numConstraints,info,debugDrawer,dispatcher);
 
 	m_tmpMultiBodyConstraints = 0;
 	m_tmpNumMultiBodyConstraints = 0;
 	
 
-}
+}
\ No newline at end of file