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P-38 Front Wheel

Anyone try a 451 front wheel?
Will it effect the steering?
I know on my Gold Rush, a 451 verus 406, improves the speed.
Thanks, Tom.

Hey Tom,

I have never tried the larger ISO 451 20" wheel on my Lightnings. If you give it a shot, be careful that you do not suffer from so-called "hard interference" between the wheel and cranks. It might happen if the crank arms are long, and the front boom is inserted all the way into the main frame for a shorter rider. Turn too sharply, and it could spoil your whole day.

If you do try it, please report back to us. It might be just fine, especially if the crank boom is extended outward.

I did try using a 451 front wheel on a Vision bike many years ago, and liked it. The bike seemed a little quicker and smoother-riding. But the Vision had the front fork tucked pretty close to the seat, so I did not have to worry about crank interference.

Safe riding,
Joel Dickman

I put a 451 front wheel on my Large size frame P-38.

There will be an article in RCN in next issue or maybe one after that.

I am 5' 7" with an x-seam of 40.5" so with the large frame I have the boom in almost all the way,which was a concern because of what you mentioned ,heel strike.

At the time I did the conversion I also had my 105 cranks shortened by Mark Stonach to 153mm.

With the short cranks there is plenty of clearance, if I had a med frame ,which also fits me, the boom would be farther out and it would work with long cranks.

I used a Paul Moto brake and I'm able to switch back and forth between the 406 and 451 wheel with only a slide adjustment of the brake pads.

I like the 451 wheel so much though ,I've never been tempted to switch back.

The only difference in handleing I've noticed is when I'm sitting still on the bike, the wheel flops over easier than before ,but once riding I notice no difference in handling.

I think I'm faster with the 451 wheel ,but at the same time some of that may be due to the shortened cranks .


Just curious to know if what has been said about the P-38 modifications are also true for an F-40. Will handling be adversely affected or enhanced? Will changing to a non-shocked front fork make a big difference in the bike?
I have an F-40 off e-bay that is my winter tinker project.

1) Because the F40 is so fast (well, at least with a rider of decent fitness), the front shock is needed. The bumps in the road that are annoying at non-faired speeds become serious problems at fully-faired speeds.

You need the front shock-absorbing fork to a) maintain control of the bike, b) provide some level of comfort, and c) preserve the fiberglass fairing's connection to the bike itself.

I would not substitute a rigid fork for the shock fork.

2) Experimenting with larger or smaller wheels can be fun. Yes, the handling will be affected. For good or ill? It is a judgement call. Most riders will probably prefer a larger diameter front wheel, as long as they can comfortably get their feet flat on the ground at stops. Doing a tip-toe balancing act with an unfaired bike is a pain. With the full fairing it is considerably worse, especially on a very windy day.

Good luck with your winter project,
Joel Dickman

At 3k miles my front shock on my new F40 wore out, and I sent it to Lightning for a rebuild.

Before I sent it, I bought the Lightning fixed fork (red, matching the bike). Had the lbs swap out the forks, so I could continue to ride while the shock was being rebuilt.

I rode the whole season with the fixed fork and found I could get by without the suspension. I ran the tire pressure between 90 and 95 psi. The fixed fork lowers the front end of the bike by about 1.5 inches, which I liked for two reasons. First, at high speeds I think the lower front end position would add a little downpressure from the airflow over the top of the fairing,to the bike - a good thing when speeds get over 40 - 45 mph.
With my inseam of 29 inches, my feet were a little closer to the ground when I stopped, so it felt like I had better balance when stopped. Both of these impressions were just that, impressions, but also seemed realistic.

Anyway, 12,000 miles later I still have not put the suspension fork back on the F40. I keep it as a back up fork, in case I would ever need one.

The Schalbe tire on the front is so tough that it seems to be able to take the pounding of higher speeds achieved with the F40.

My dealer, Tyger Johnson, is a racer, and he has never used a suspension fork on either of his F40s. He rides way faster, and way more miles than I do with his fixed fork.

So IMHO, the suspension fork is optional, and I do miss the suspension a little, but it needed a lot of adjustment every 100 - 200 miles, which I don't miss. YMMV.

As Ken / Blue F40 points out, the shock fork a) raises the front end of the bike some, and b) will require more fiddling with than a rigid fork. (Don't know about aero differences.) It costs more than a rigid fork and weighs more too.

If a rigid fork is good enough for Tyger Johnson's F40, it ought to be good enough for anyone. Tyger is a very accomplished bicycle racer, often beating much younger riders.

One variable we have left out is road conditions. I ride in the Chicago area, where roads are often in poor shape. So I like suspension - both front and rear - and fatter tires. Since the topography is mostly flat, the additional weight is no big deal.

Guess I'm getting old. The Cadillac ride is appealing.

Suppose that most of your riding is in an area with nice smooth roads. Then getting rid of suspension and using higher pressure tires makes sense. Especially if you have to to ride up steep hills.

Safe riding,
Joel Dickman

Hi Ben, thanks for the description.

Curious about what fork you are using though. Is it an ordinary Lightning 20" fork, or something else?

If you are using a Lightning fork, is there enough clearance for fatter ISO 451 tires and fenders, or is it too tight?

Safe riding,
Joel Dickman

Yes there's tons of room with the stock 20" fork. I can send you a picture if you give me your e-mail.

Please send along a nice clear picture at:

The more pictures of Lightning bikes, especially unusual ones, the better.



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