Wanted: Ionger travel inline Ceriani forks

[tooclose racing]

A few of you may have seen my FB post. I'm thinking about moving to a longer travel (inline) Ceriani fork for my 74.5 Jackpiner for Historic class racing.  From the feedback received, sounds like there were one or two styles that were sold on the 76 or 77 GS "cross country" style bikes or early Hercules models, one with a reinforcing rib, maybe one without. I'm guessing these models - while 35mm - might require their own unique triple clamps. I would rather not go to the leading axle style (like on my 76 MC5).  This is an exploratory inquiry.  Thanks! 

Bob Close
AHRMA #567
Several Pentons  ; -)

[Doug Knight]

The '74 should have come with 35mm with 7 inches of travel. I have 6-75 250 with the ribbed 35mm inline with 8" travel. The triple trees should fit with the upper tree as is also tapered.

My '74 125 also came with those 35mm early 250 forks with 7 inches of travel.

Make note here that extending or shorting the forks you change the steering angle. Too long slow turning (good for high speed). Shorter or shallow angle (good for tight turning woods action).

I have never seen a '76 model of any kind. Have had '77 and '78 which had 38mm Marzzoici leading axles

[Carl Hill]

I have a set I've been saving for future project. Hadn't thought about selling but I suppose could if the price was right

[Daniel P. McEntee]

  If I understand what you are talking about, these are the Ceriani's that the triple clamp centers for the upper tubes are in a straight line with the triple clamp pivot? I have a 400 with these forks ( they came with the bike,) and the one issue to contend with is it really limits the "lock to lock" movement of the forks and will limit how tight you can turn. I haven't dealt with mine yet but as I see it I will have to cut down the fork stop tubes on the frame. My frame is a 74.5 or 75 year model. If you do that, then if you co back to stock forks, the upper tubes will hit the tank, and you will need to restore what ever was cut off. I think I'm understanding this correctly.
  Type at you later,
   Dan McEntee

[skiracer]

Hey Bob,
So yes, the 1976 XC models did have the longer straight forks on them.  My 175, and a 250 I had came with them.  They are know as the 200's, indicating the length of travel; 200mm or 7.9".  They have the tapered tops so they will slide into the triples on your 74.5.  Axle should be the same as your existing too.  Just remember, you will need to install longer shocks to compensate for the change in travel length on the front.  I would recommend the laydown position for better shock life and handling.  Some of the forks have the "200" stamped in the lower section near the axle holes.  What happened to your 1977 GS? That is the perfect bike for the Historic class....

[tooclose racing]

Thanks for the replies guys!

@ Doug Knight - you are absolutely right about my 74.5 35 mm forks being 7 inches of travel and I'm kind of embarrassed about not knowing or having ever confirmed that when i have done oil change or seal maintenance.  And with respect to longer front travel changing steering angle - I hear you.  Two things - I'm going to move my shocks to the laydown position, which would tend to counter that effect, I think I have noticed a tiny difference (sharper turning) when I have ran the shocks in that position before. And that is also one of the reasons I want to run an inline fork, I think a leading axle (AND longer travel) fork (with requisite clamps probably being required) would tend to slow down the steering.  I have raced two MC5s in hare scrambles (175 and 250) that I think don't turn nearly as sharply as my Jackpiner.  Could be wheelbase, longer travel, but I also think that leading axle fork contributes.  I wonder if the late and great world GP champ Moissev (RIP) would have agreed.

@ski racer - thank you James (again) for the edu-ma-cation regarding those inline "200" Ceriani forks. And thrilled to here they use that unique (it least it seems that way to me...) tapered upper tube.  Now - where the hell would I find a pair of those??

But...it's possible adding that much travel might slow steering down without increasing shock length of my Works shocks in the back, even in laydown (the 13.5 works great in lay-down and 'traditional").  As for my 77 MC5 175 build that has been my Historic racer for 3-4 years, I think I'm gonna sell it, currently making it pretty in the garage after a half (hearted) season on it in 2022.  You have heard me complain about the Gen 2 175 engine characteristics (i.e. the 7 fin motor) being way different than the six fin and it took me a long time to start going faster on the bike, even with the excellent MC5 suspension. I've always felt faster on my Jackpiner and - taking into account a 2nd XC race on the day might slow my ass down a bit (sometimes a LOT), when there was timed scoring, it confirmed this.  Hilarious right?  Thus my "vision" to try some Historic class racing with a (possibly) longer travel Jackpiner. Final comment on my 77 MC5 175 - l LOVE doing the occasional MX on it. It's real home in many ways, I keep up with bikes a lot bigger than mine.  I hope you and yours are healthy in Florida, sir. 

[skiracer]

Soooo, a couple of points to think about.  I would be sure to get a set of forks that have the re-inforced rib on the front.  The early models did not have the rib, and I heard about issues with tube bending/failure.  They didn't put the rip on there for the look.  My 76 XC 175 is very close to your 74.5 frame wise and I know the steering is quicker than the MC5 frames; and thats with the longer suspension from yours.  I wouldn't worry about that aspect of it. Its not like you are adding 4" of travel to the bike.  One drawback to the taper tubes, is that you can't slide the tubes up in the triples to tighten the steering for a particular race. Anyway, your ideas are correct, keep moving in that direction, you'll love it.  Where to find a set is the question.  When you do find a pair, play around with the oil in them.  I like running lighter (10W) oil with higher volume as to heavier oil less volume.  I run the oil about 5" from the top to help with the bottoming out... Just my thoughts. Yes, things are good here in Florida; my riding season started last month, and the storms seem to have missed us again.  Hope you and your wife are well, yes(?)

[Doug Knight]

In the past 6 months I have seen 2 sets of front ribbed 8" travel  Cerianis on Ebay, make sure you are also looking in their European feeds as you may miss a set. Don't bitch when you find a set, they are priced as gold.

[tooclose racing]

Thanks again guy (@Ski, @Doug)