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Loose steering tube returns

My 2001 P38 was down for two years with a loose steerer that no amount of tightening or a coke can shim could correct. A bike mechanic friend
looked at it recently and determined that there was more grip surface available than the single bolt seat clamp was using. He installed a wider, 2 bolt Rans or Baccheta type clamp and that worked for a couple of months. This morning the steerer wa acting independently from the forks again. Has anyone been able to permanently solve this problem?

Thanks,
Carolyn

Hi Carolyn,

On the older Lightning P-38 bikes I have owned, the stem / steering column / handlebar was a single piece of aluminum. The stem seemed to be machined and the steering column / handlebar was welded aluminum tubing. I think Loctite - or some other adhesive - was used to join the machined stem to the aluminum tube steering column.

The threaded fork steerer tube had a little slot cut into it, and the machined aluminum stem was inserted inside the fork. A clamp that looked like a seatpost clamp was used to compress the top of the fork steerer tube so that the slotted portion gripped the stem and held everything together. I never had any slipping problems with my bikes of the kind you describe. Maybe the surface of the stem - the part that gets inserted inside the fork steerer - got contaminated with lubricant somehow? Have you tried thoroughly cleaning all the mating metal surfaces with solvent to eliminate this possibility? It is hard to diagnose bike mechanical problems over email...

Your slipping problem is a mystery to me. Maybe a phone call or an email to Lightning would help? Please write back and let us know what you have tried, what helps and what does not, and what Lightning suggests.

And DO NOT ride the bike until you get the problem solved!

Safe riding,
Joel

Hi Joel,
We have talked to both Tim and Brian. There have apparently been several designs for the steerer/fork assembly. The responses were pretty vague even when a mechanic was asking the questions. Brian suggested I take my 2005 P38 apart to see what it looks like inside, like I will ever take a functioning front end apart now.

We have cleaned, shimmed, and tried a wider seat clamp, which did last a couple of months, but slipped yesterday and cannot be tightened enough to stop slipping.

This bike is a 2001, so the bars aren't welded. At this point, we are looking at ordering a fork and steerer unless anyone can think of another solution. We thought of industrial loctite but it requires a torch.

thanks for your input,
Carolyn

Here's what I used soon after buying my P38
http://poweroncycling.com/product/poc-stem-clamp-459.htm
Howard

Thanks Howard, that looks like the seat clamp we retrofitted as well.

Carolyn

I believe your problem is not the mast slipping on the steer-tube but the steer-tube slipping inside the fork. I think someone tried to explain this earlier in this thread. My solution was to remove the aluminum steer-tube from the fork, file the bottom angled to fit a conventional jam-nut and re introduce the tube into the fork now secured with the jam-nut and long bolt(donored from an old DF) never to crash again. Your LBS can probably help you with used parts. If not; try an un-ladylike cruse of your neighborhood on trash day. Most DFs (including kid's bikes) have their steering secured in this manner.

Thanks, I'm going to copy and paste that to my mechanic.Thank you!

OK, what we found is a 3.25" tube brazed into the top of the fork. No way to insert the 7/8" quill that should be there. Has anyone seen anything like this before???

http://i874.photobucket.com/albums/ab302/ctrim/IMG_0239_zps9afc05be.jpg

http://i874.photobucket.com/albums/ab302/ctrim/IMG_0238_zps25bcdca4.jpg

http://i874.photobucket.com/albums/ab302/ctrim/IMG_0237_zpsa513c3c4.jpg

the jpegs above show the soldered tube the steerer was clamped to.

Hi again Carol,

I remember having a Lightning fork like yours many moons ago, with a tube stuck inside the fork steerer tube. But mine was not brazed inside, it was glued in with Loctite or some other adhesive. Tim Brummer told me to heat the fork over my stove for awhile, and that allowed the adhesive to melt. I was then able to pull the tube out of the top of the fork. It was not easy to pull out, even after heating up the fork steerer over the stove. But eventually I managed to remove it.

This was a long time ago.

Clearly there are multiple ways that Lightning constructs the steering system on the P-38. My older bikes are not put together like yours, and I am not clear about how your bike works. So I unfortunately cannot be of much help here.

But Tim Brummer or Brian should be able to solve your problem easily. If you are not a mechanical person, and have someone else service your bike, maybe your helper needs to discuss further with Lightning to get this mess sorted out.

Keep talking to Lightning - or have your mechanic keep talking - until the bike gets fixed properly and you can ride it again. It is too nice a machine to allow to remain idle.

Good luck with it, and don't give up!

Safe riding,
Joel

Thanks Joel, it's helpful to hear that someone has seen this oddball configuration before :-) My mechanic/friend wanted me to bring the bike over after seeing the pictures and my finding the quill Tim sent us a couple of years ago, but I couldn't get there before he and his wife left. Soon as he gets back from Colorado we'll get her (the P38) back on the road.
The phone conversations with Lightning did not garner any information about alternate fork/steerer configurations. Thank goodness this is my backup/rough duty bike; my main ride P38 functions perfectly.

Thanks again,
Carolyn

Carolyn, Sorry I wasn’t auditing this thread since my entry. Your photos seem to depict exactly the same configuration of my 99 P38 XL; An Aluminum steer tube inserted into a steel fork stem and fastened with an industrial adhesive. (Brazing or soldering would not likely have been used or been effective.) If you were to draw a witness mark vertically from the fork stem onto the steer tube (Sharpie) and then clamp your mast and bars high enough to watch the tube you should be able to observe the tube slip within the stem. (holding the wheel between your knees while twisting the bars) If this is what occurs, pull up on the bars until the tube pulls clear of the fork. If that proves too difficult, apply heat to the tube with a hair dryer or torch. At 400~425F. the adhesive should release completely and then you can follow the instructions in my previous post.

Thanks Dave, will do.I just hope my 2005 isn't put together the same way :-)

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