Help -- is there anyway to stiffen front forks of a crf70 with out replacing?

Not all front suspension forks are adjustable, but if yours is, you should find adjusting nuts on the shocks. Check with the manufacturer if in doubt.

Sorry to inform you, but there is no adjustments available for the forks that come with your bike. Adjustable forks (just the fork) start in around $250-.

On the positive side since there is not adjustment capability the fork does not need regular servicing like the adjustable forks.

If you remove the front wheel, front brake caliper, and front fender and look on the very bottom of the slider where the axle came out, you'll see an 8mm socket head bolt. If you remove this bolt, the slider will come off.

But before you do that, I'd advise draining the oil from the fork leg and releasing the spring tension on the slider by removing the fork tube plug and removing the spring. To get to this plug, you'll probably have to remove the windshield, the nachelle, and the top cap. Then loosen the clamp bolt in the lower triple tree and allow the fork to slide down and out of the triple trees.

When you refill the fork with oil. Use the same amount and viscosity as what was in there. Thicker viscosity and more oil has a tendency to "stiffen" the fork.

Good Luck
Steve

If it has air caps on the top of the forks, you can put a little air in them. If not, the other thing you can do is add a bit more oil to each fork leg.

Does it have a bad fork seal? Check this by popping the dust cover off the lower legs and if you see fork oil on top of the seal than it has gone dad and needs replaced. Adding oil to the forks will stiffen then back up but if you have bad seals then you will be adding more oil again in a very short time and also this is dangerous cause the oil can get on the brake pads and cause brake fade when you need them.
Good luck.

i prepared it to be soft for comfortable riding but if you think that it is to soft try to add some air on it, but check the oil seal of the fork if it has no leak.

no you can change the seal and the oil just make sure you measure the oil you remove and put the same amount back in