http://www.cyclexchange.net/
Thanks Davez,
I called cyclex and got to speak w/ the owner Ken and he told me that he didn't carry any tubes for the CB400F but said that if he noticed there was more of a 'call' for them or if they fit other bikes that he will consider carrying them.
I mentioned the CB350F has the same diameter and style of fork tubes as the CB400F but a little different length;the same dia. and style of fork tubes are also used in the CB350 twins & 400 Hawk models but different length's.
I think I got Ken's attention
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He said I'm the only guy in 20 yrs. that asked for fork tubes for the CB400F so let's have a few more of you CB400F and 350F owners call him up !! The difference in price between Frank's Engineering is double what you can get them from Ken and Frank's is very tough to reach to even make an order.
Ken @ Cyclex said that he needs to hear from more of us small Honda four owners before he can fulfil the requirements of a minimum order so lets call him up !
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Ring his bell and he'll start carrying 33mm fork tubes !